flarenet modelling
DESCRIPTION
Useful manualTRANSCRIPT
Reference Manual
Aspen Flare System Analyzer
Version: V7.3March 2011
Copyright (c) 1981-2011 by Aspen Technology, Inc. All rights reserved.
Aspen Flare System Analyzer, Aspen Flarenet, Aspen Plus, Aspen HYSYS, Aspen Plus Dynamics, andthe aspen leaf logo are trademarks or registered trademarks of Aspen Technology, Inc., Burlington,MA. All other brand and product names are trademarks or registered trademarks of their respectivecompanies.
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Contents i
Contents
1 Introduction.........................................................................................................1
About this document.........................................................................................1Audience.........................................................................................................1Related Documentation.....................................................................................1Technical Support ............................................................................................1
2 Components .........................................................................................................3
Overview.........................................................................................................3Selecting Components ......................................................................................4
Component Types ..................................................................................4Component List......................................................................................4Matching the Name String .......................................................................5Removing Selected Components ..............................................................5
Adding/Editing Components...............................................................................6Add Hypothetical Component/Edit Component ...........................................6Identification Tab ...................................................................................6Critical Tab............................................................................................7Other Tab..............................................................................................9Editing Database Components .................................................................9Estimating Unknown Properties.............................................................. 10
Organizing the Component List ........................................................................ 11Changing the Components .................................................................... 11Combining Components ........................................................................ 11
Binary Interaction Parameters ......................................................................... 11
3 Scenarios ...........................................................................................................15
Overview....................................................................................................... 15Scenario Manager .......................................................................................... 16Adding/Editing Scenarios................................................................................. 17
General Tab......................................................................................... 18Constraints Tab.................................................................................... 19Sources Tab ........................................................................................ 20Estimates Tab...................................................................................... 21
Scenario Tools ............................................................................................... 23Adding Single Source Scenarios ............................................................. 23
4 Pipe Network......................................................................................................25
Overview....................................................................................................... 25Pipe Manager................................................................................................. 25Ignoring/Restoring Pipes ................................................................................. 26
Connections Tab .................................................................................. 27Dimensions Tab ................................................................................... 29
ii Contents
Fittings Tab ......................................................................................... 30Heat Transfer Tab ................................................................................ 32Methods Tab........................................................................................ 33Summary Tab ...................................................................................... 37Multiple Editing .................................................................................... 38Pipe Class Editor .................................................................................. 39
5 Nodes.................................................................................................................41
Overview....................................................................................................... 41Node Manager ............................................................................................... 41Ignoring/Restoring Nodes................................................................................ 42Connection Nodes .......................................................................................... 43
Connector ........................................................................................... 43Flow Bleed........................................................................................... 47Horizontal Separator............................................................................. 50Orifice Plate......................................................................................... 56Tee .................................................................................................... 60Vertical Separator ................................................................................ 65Summary Tab ...................................................................................... 70
Boundary Nodes............................................................................................. 71Control Valve....................................................................................... 71Relief Valve ......................................................................................... 81Source Tools........................................................................................ 94Flare Tip ............................................................................................. 95
6 Calculations......................................................................................................101
Starting the Calculations ............................................................................... 101Efficient Modeling Techniques ........................................................................ 102
Data Entry......................................................................................... 102Calculation Speed............................................................................... 103Sizing Calculations ............................................................................. 104
7 Databases ........................................................................................................107
Overview..................................................................................................... 107Database Features ....................................................................................... 108
Grid Controls ..................................................................................... 108Maneuvering Through the Table ........................................................... 109Printing............................................................................................. 109Adding/Deleting Data.......................................................................... 109
Setting The Password ................................................................................... 110Pipe Schedule Database Editor....................................................................... 110Fittings Database Editor ................................................................................ 112Component Database Editor .......................................................................... 112
Importing Component Data ................................................................. 113
8 Automation ......................................................................................................115
Overview..................................................................................................... 115Objects ....................................................................................................... 116
Object Hierarchy ................................................................................ 116The Aspen Flare System Analyzer Type Library ...................................... 117Object Browser .................................................................................. 117
Contents iii
Automation Syntax............................................................................. 120Examples: Accessing Aspen Flare System Analyzer Object Properties ....... 123
Aspen Flare System Analyzer Object Reference................................................ 126Application ........................................................................................ 127Bleed................................................................................................ 128Bleeds .............................................................................................. 128Component........................................................................................ 129Components ...................................................................................... 130Connector ......................................................................................... 130Connectors........................................................................................ 131ControlValve...................................................................................... 132ControlValves .................................................................................... 133HorizontalSeparator............................................................................ 133HorizontalSeparators .......................................................................... 134Nodes ............................................................................................... 134OrificePlate........................................................................................ 135OrificePlates ...................................................................................... 135Pipe.................................................................................................. 136Pipes ................................................................................................ 138ReliefValve ........................................................................................ 139ReliefValves....................................................................................... 141Scenario ........................................................................................... 141Scenarios .......................................................................................... 142Solver............................................................................................... 142Tee .................................................................................................. 143Tees ................................................................................................. 144Tip ................................................................................................... 145Tips.................................................................................................. 146VerticalSeparator ............................................................................... 146VerticalSeparators.............................................................................. 147
Example – Automation In Visual Basic ............................................................ 147Updating Automation Files From Previous Versions ........................................... 155
9 Theoretical Basis ..............................................................................................157
Pressure Drop.............................................................................................. 157Pipe Pressure Drop Method.................................................................. 157Fittings Pressure Change Methods ........................................................ 165
Vapor-Liquid Equilibrium ............................................................................... 175Compressible Gas............................................................................... 175Vapor Pressure .................................................................................. 175Soave Redlich Kwong.......................................................................... 176Peng Robinson ................................................................................... 177
Physical Properties ....................................................................................... 178Vapor Density .................................................................................... 178Liquid Density.................................................................................... 178Vapor Viscosity .................................................................................. 179Liquid Viscosity .................................................................................. 179Liquid Phase Mixing Rules for Viscosity.................................................. 181Thermal Conductivity.......................................................................... 182Enthalpy ........................................................................................... 182
Noise .......................................................................................................... 186
iv Contents
A File Format.......................................................................................................189
Import/Export Details ................................................................................... 189Process Descriptions........................................................................... 189Definition File Formats ........................................................................ 192Recognized Objects and Items ............................................................. 197
Report Files Format ...................................................................................... 215
B References .......................................................................................................221
C Glossary of Terms ............................................................................................223
Adiabatic Flow ............................................................................................. 223Choked Flow................................................................................................ 223Critical Pressure ........................................................................................... 223Critical Temperature ..................................................................................... 223Dongle........................................................................................................ 223Equivalent Length ........................................................................................ 223Isothermal Flow ........................................................................................... 224MABP.......................................................................................................... 224Mach Number .............................................................................................. 224Node .......................................................................................................... 224Reduced Pressure......................................................................................... 224Reduced Temperature................................................................................... 224Scenario ..................................................................................................... 224Schedule..................................................................................................... 225Security Device............................................................................................ 225Source ........................................................................................................ 225Static Pressure............................................................................................. 225Tailpipe....................................................................................................... 225Total Pressure.............................................................................................. 225Velocity Pressure.......................................................................................... 225
Index ..................................................................................................................226
1 Introduction 1
1 Introduction
This section provides information on the following topics:
About this Document
Audience
Related Documentation
Technical Support
About this documentThe guide provides a detailed description of all the features and functionalitywithin Aspen Flare System Analyzer (previously called Aspen FLARENET).
AudienceThis guide is intended for process and process systems engineers.
Related DocumentationTitle Content
Aspen Flare System AnalyzerGetting Started Guide
Tutorials covering the basic use of AspenFlare System Analyzer
Technical SupportAspenTech customers with a valid license and software maintenanceagreement can register to access the online AspenTech Support Center at:
http://support.aspentech.com
This Web support site allows you to:
Access current product documentation
Search for tech tips, solutions and frequently asked questions (FAQs)
Search for and download application examples
2 1 Introduction
Search for and download service packs and product updates
Submit and track technical issues
Send suggestions
Report product defects
Review lists of known deficiencies and defects
Registered users can also subscribe to our Technical Support e-Bulletins.These e-Bulletins are used to alert users to important technical supportinformation such as:
Technical advisories
Product updates and releases
Customer support is also available by phone, fax, and email. The most up-to-date contact information is available at the AspenTech Support Center athttp://support.aspentech.com.
2 Components 3
2 Components
This section provides information on the following topics:
Overview
Selecting Components
Adding/Editing Components
Organizing the Component List
Binary Interaction Parameters
OverviewData for all components that will be used in the simulation must be selectedbefore the sources are defined. These components may be taken from thestandard component library, or you may define your own components, knownas hypothetical components.
You may select components from Component Manager, which can beaccessed by clicking Components in the Build group on the Home tab of theRibbon.
The Component Manager window will be displayed:
4
Fig 2.1
This view displays all of theComponents, and provides various tools which you can use to add and editdatabase and hypothetical components.
Selecting Components
Component TypesYou may filter the list of available components to include only those belongingto a specific family.respectively, Invertexample, if only HydrocarbonsInvert, then these two check boxes would be cleared, while the remainingcheck boxes would be
Component ListComponents can be chosen from theto the Selected C
1 Arrow Keyscomponent.
2 PageUp/PageDownpage forward or backward.
This view displays all of the Available Components and Selected, and provides various tools which you can use to add and edit
and hypothetical components.
Selecting Components
Component TypesYou may filter the list of available components to include only those belongingto a specific family. All and None turn all of the filters on and off,
Invert toggles the status of each check box individually. As anexample, if only Hydrocarbons (HC) and Misc were selected, and you clicked
, then these two check boxes would be cleared, while the remainingcheck boxes would be selected.
Component ListComponents can be chosen from the Available Components
Components list, using one of the following methods:
– Use the arrow keys to move the highlight up or down one
PageUp/PageDown - Press these keyboard keys to advance an entirepage forward or backward.
2 Components
Selected, and provides various tools which you can use to add and edit
You may filter the list of available components to include only those belongingand off,
box individually. As anwere selected, and you clicked
, then these two check boxes would be cleared, while the remaining
list, and addedlist, using one of the following methods:
to move the highlight up or down one
Press these keyboard keys to advance an entire
2 Components 5
3 Home/End - Press Home to move to the start of the list and End tomove to the end of the list.
4 Scroll Bar - Use the scroll bar to move up and down through the list.
Note: You can select multiple components by using the SHIFT or CTRL keys asyou select components.
5 Enter the component name from keyboard - When you type a letteror number, you will move to the next component in the list which startswith that character. If you repeatedly enter the same character, you willcycle through all of the components which start with that character.
To add a component, you must first highlight it (by moving through the listuntil that component is highlighted) and click to select, then transfer it bydouble-clicking it or clicking Add.
Matching the Name StringThe interpretation of your input is limited to the Component Types whichare checked.
Another way to add components is through the Selection Filter feature. TheSelection Filter box accepts keyboard input, and is used to locate thecomponent(s) in the current list that best matches your input.
You may use wildcard characters as follows:
? - Represents a single character.
* - Represents a group of characters of undefined length.
Any filter string has an implied * character at the end.
Some examples are shown here:
Filter Result
methan methanol, methane, etc.
*anol methanol, ethanol, propanol, etc.
?-propanol 1-propanol, 2-propanol
*ane methane, ethane, propane, i-butane, etc.
As you are typing into the Selection Filter box, the component list isupdated, matching what you have presently typed. You may not have to enterthe complete name or formula before it appears in the component list.
Removing Selected ComponentsYou can remove any component from the Selected Components list:1
Highlight the component(s) you want to delete.
2 Click Remove.
You can select multiple components using Shift-click and Ctrl-click to removethem all. Once the components are removed from the list, any sourcecompositions that used this component will be normalized.
6
Adding/Editing ComponentsTo create a new component (hypothetical), clickcomponents are set up in thPreviously defined hypothetical components can be changed by selectingthem in the Selected Component
Add Hypothetical Component/EditComponentUpon clicking either
Identification TabThe minimum data requirements for creating a component are specified here
Fig 2.2
Component Types
Hydrocarbon (
Miscellaneous (
Amine
Adding/Editing ComponentsTo create a new component (hypothetical), click Hypotheticalcomponents are set up in the same manner as database components.Previously defined hypothetical components can be changed by selecting
Selected Components list and clicking Edit.
Add Hypothetical Component/EditComponentUpon clicking either Hypothetical or Edit, the Component Editor
Identification TabThe minimum data requirements for creating a component are specified here
Component Types
Hydrocarbon (HC)
Miscellaneous (Misc)
2 Components
Adding/Editing ComponentsHypothetical. Hypothetical
e same manner as database components.Previously defined hypothetical components can be changed by selecting
mponent Editor opens up.
The minimum data requirements for creating a component are specified here:
2 Components 7
Alcohol
Ketone
Aldehyde
Ester
Carboxylic Acid (Carbacid)
Halogen
Nitrile
Phenol
Ether
The following fields are available on this tab:
Input Field Description
Name An alphanumeric name for the component (e.g. - Hypo -1).
Type The type of component (or family) can be selected from the listprovided. There is a wide selection of families to choose from, whichallows better estimation methods to be chosen for that component.
ID The ID number is provided automatically for new components andcannot be edited.
Mol. Wt. The molecular weight of the component.
NBP The normal boiling point of the component.
Std. Density The density of the component as liquid at 1 atm and 60 F.
Watson K The Watson characterization factor.
Critical TabCritical properties are specified here.
8
Fig 2.3
The following field
Input Field
Critical Pres.
Critical Temp.
Critical Volume
Char. Volume
Acentric Factor
Acent. Fact. (SRK)
The following fields are available on this tab:
Description
The critical pressure of the component. If the componentrepresents more than a single real component, the pseudocritical pressure should be used.
The critical temperature of the component. If the componentrepresents more than a single real component, the pseudocritical temperature should be used.
The critical volume of the component. If the componentrepresents more than a single real component, the psecritical volume should be used.
The characteristic volume of the component. If the componentrepresents more than a single real component, the pseudocharacteristic volume should be used.
The acentric factor of the component.
Acent. Fact. (SRK) The Soave-Redlich-Kwong acentric factor of the component(also called the COSTALD Acentricity).
2 Components
The critical pressure of the component. If the componentrepresents more than a single real component, the pseudo
e of the component. If the componentrepresents more than a single real component, the pseudo
The critical volume of the component. If the componentrepresents more than a single real component, the pseudo
The characteristic volume of the component. If the componentrepresents more than a single real component, the pseudo
Kwong acentric factor of the component
2 Components
Other TabCoefficients for the polynomial equations for the prediction of Ideal Gasthermodynamic properties and parameters for the vispecified here:
Fig 2.4
The following fields are available on this tab:
Input Field
Hi A, Hi B, Hi C, Hi D, Hi E, andHi F
Entropy Coef.
Viscosity A and Viscosity B
Editing Database ComponentsIf you want to change the data for one of the database components, e.g.Methane, you will find thatcomponent will display
Other TabCoefficients for the polynomial equations for the prediction of Ideal Gasthermodynamic properties and parameters for the viscosity calculations are
The following fields are available on this tab:
Description
Hi A, Hi B, Hi C, Hi D, Hi E, and The coefficients for the ideal gas specific enthalpyequation:
The coefficient for the entropy equation.
Viscosity A and Viscosity B Viscosity coefficients used in the NBS Method (Elyand Hanley, 1983).
Editing Database ComponentsIf you want to change the data for one of the database components, e.g.Methane, you will find that opening the Component Editor for thiscomponent will display read-only values that cannot be changed.
Hi
A BT CT2 DT3 ET4 FT+ + + + +=
9
Coefficients for the polynomial equations for the prediction of Ideal Gasscosity calculations are
The coefficients for the ideal gas specific enthalpy
nt for the entropy equation.
Viscosity coefficients used in the NBS Method (Ely
If you want to change the data for one of the database components, e.g.for this
values that cannot be changed.
FT5
10
Fig 2.5
In order to update the data for a database component it must first bechanged to a hypothetical comp
At the very minimum, you need to specify the Molecular Weight. However, itis a good practice to specify at least two of the following properties:
Molecular Weight (
Normal Boiling Point (
Standard Density (
This is done by clicking
Estimating Unknown PropertiesIf any of the above data is unknown, clickproperties.
Supply as many properties as are known, soaccurate as possible.
In order to update the data for a database component it must first bechanged to a hypothetical component.
At the very minimum, you need to specify the Molecular Weight. However, itis a good practice to specify at least two of the following properties:
Molecular Weight (Mol. Wt.)
Normal Boiling Point (NBP)
Standard Density (Std. Density)
clicking Hypothetical in the Component Editor
Estimating Unknown PropertiesIf any of the above data is unknown, click Estimate to fill-in the unknown
Supply as many properties as are known, so that the estimation can be asaccurate as possible.
2 Components
In order to update the data for a database component it must first be
At the very minimum, you need to specify the Molecular Weight. However, itis a good practice to specify at least two of the following properties:
Component Editor.
in the unknown
that the estimation can be as
2 Components 11
Organizing the Component ListThe Selected Components list can be organized in the following differentways.
Changing the ComponentsYou can switch the components in the Selected Components list with theones in the Available Components list while maintaining the source molefractions.
In Component Manager, select the components in both the SelectedComponents and the Available Components lists. Click Switch to switchthe two components.
Combining ComponentsMultiple components can be combined and represented by a single componentto reduce the number of components in the model.
To combine multiple components:
1 Select the components you want to combine by Ctrl-clicking them in theSelected Components list.
2 Click Combine.
The Component Combination window will be displayed, and ask you toselect which basis should be used. The highlighted component in the boxat the upper part of the window is the target component to combine yourselected components into. Once the basis has been selected the combinedcomponents will update each source in the model by summing thecomposition of all of the combined components and assigning it to thetarget component.
Reducing the number of components in this way is useful since it can greatlyspeed the calculations. This is especially true where a model contains sourcesdefined with a long list of hypothetical components.
For example, consider a model containing the hypothetical componentsBP200, BP225, BP250, BP275, BP300 boiling at 200°C, 225°C, 250°C, 275°Cand 300°C respectively. Since these components are likely to stay in theliquid phase throughout the flare system, they may be combined into a singlecomponent, BP250 without significant loss of accuracy. As another example,in a purely gas phase flare system it is possible to combine isomers such as i-Butane and n-Butane into a single component n-Butane withoutcompromising results.
Binary Interaction ParametersBinary Interaction Coefficients, often known as KIJ’s, are factors that are usedin equations of state to better fit the interaction between pairs of componentsand hence improve the accuracy of VLE calculations. You are allowed tospecify binary interaction parameters for the Peng Robinson and Soave
12
Redlich Kwong VLE methods or to estimate them through thetab of the Component Manager
Fig 2.6
To define binary interaction coefficientsRobinson or Soave Redlich Kwongat the top of the window.
Note: Binary interacCompressible Gas
Individual binary interaction parameters are set by selecting the requiredentry in the matrix and typing in the new value.
Note: The matrix is symmetrian entry will also update the corresponding entry in the table. E.g. updatingthe entry in the Methane column, Propane row will also update the entry inthe Propane column, Methane row.
Individual binaryrequired entry in the matrix and clickingmethod is based on the componentscritical volume.
It is possible to set several binaeither by Ctrl-clicking the two corners of a rectangular area in the matrix. Theselected entries can then be estimated by clickingby clicking Zero HC
Redlich Kwong VLE methods or to estimate them through the Binary CoeffsComponent Manager as shown here.
To define binary interaction coefficients, first select either theSoave Redlich Kwong VLE method from the VLE Method
at the top of the window.
Binary interaction coefficients are not used by either theGas or Vapor Pressure VLE methods at present
Individual binary interaction parameters are set by selecting the requiredentry in the matrix and typing in the new value.
The matrix is symmetrical i.e. KJI is the same value as Kan entry will also update the corresponding entry in the table. E.g. updatingthe entry in the Methane column, Propane row will also update the entry inthe Propane column, Methane row.
Individual binary interaction parameters may be estimated by selecting therequired entry in the matrix and clicking Estimate HC. The estimationmethod is based on the components' boiling point, standard liquid density and
It is possible to set several binary interaction parameters at the same timeclicking the two corners of a rectangular area in the matrix. The
selected entries can then be estimated by clicking Estimate HCZero HC-HC.
2 Components
Binary Coeffs
first select either the PengVLE Method list
tion coefficients are not used by either theVLE methods at present.
Individual binary interaction parameters are set by selecting the required
is the same value as KJI, and updatingan entry will also update the corresponding entry in the table. E.g. updatingthe entry in the Methane column, Propane row will also update the entry in
interaction parameters may be estimated by selecting the. The estimation
boiling point, standard liquid density and
ry interaction parameters at the same timeclicking the two corners of a rectangular area in the matrix. The
HC or set to 0.0
2 Components 13
Clicking Reset All causes all interaction parameters to be set to their defaultvalues. Generally this is 0.0 for hydrocarbon components with non zerovalues being supplied only for common polar components.
If the Auto Estimate check box is selected, then the interaction parametersfor new components are automatically estimated as they are added to themodel.
14 2 Components
3 Scenarios 15
3 Scenarios
This section provides information on the following topics:
Overview
Scenario Manager
Adding/Editing Scenarios
Scenario Tools
OverviewA scenario defines a set of source conditions (flows, compositions, pressuresand temperatures) for the entire network. The design of a typical flare headersystem will be comprised of many scenarios for each of which the headersystem must have adequate hydraulic capacity. Typical scenarios mightcorrespond to:
Plant wide power failure
Plant wide cooling medium or instrument air failure
Localized control valve failure
Localized fire or Depressurization
The scenario management allows you to simultaneously design and rate theheader system for all of the possible relief scenarios.
Note: Although the major relief scenarios will normally constrain the size ofthe main headers, care should be taken in the evaluation of velocities in theindividual relief valve tailpipes and sub headers. When looking at relief valveswhich might operate alone, lower back pressures in the main headers maylead to localized high velocities and consequently choked flow in the tail pipes.
As well as having different source conditions, each scenario can have uniquedesign limitations that will be used either to size the pipes or to highlightproblems when an existing flare system is being rated. For example, a Machnumber limit of 0.30 might be applied for normal flaring compared to a Machnumber limit of 0.50 or greater at the peak flows encountered during plantblowdown.
16 3 Scenarios
Scenario ManagerScenarios can also be selected by selecting the scenario from the list in Rungroup on the Home tab of the Ribbon.
Fig 3.1
Scenarios are managed via the Scenario Manager. This window allows youto add, edit or delete scenarios as well as to select the current scenario forwhich scenario specific data is displayed. All cases have at least one scenario.
To access the Scenario Manager
On the Home tab, in Build, click Scenarios.
Scenario Manager will be displayed:
3 Scenarios
Fig 3.2
The Scenario Managercurrent scenario. Several buttons are available:
Button
Clone
Edit
Delete
Current
Close
Adding/Editing ScenariosAspen Flare System Analyzer has no prescenarios which can
To add a scenario,then click Clone
To edit a scenario, highlight it, and then click
The Scenario Editor
Scenario Manager displays all scenarios in the case, and indicates thecurrent scenario. Several buttons are available:
Description
Clones the highlighted scenario and adds a new scenario tothe Scenarios list.
Edits the highlighted scenario.
Removes the currently highlighted scenario. There mustalways be at least one scenario in the case.
To make a scenario the current one, highlight the appropriatescenario, and then click Current.
Closes the Scenario Manager.
Adding/Editing ScenariosAspen Flare System Analyzer has no pre-programmed limits on the number ofscenarios which can be defined within a single case.
To add a scenario, highlight a existing scenario in the Scenariosin the Scenario Manager.
To edit a scenario, highlight it, and then click Edit.
The Scenario Editor will be displayed.
17
displays all scenarios in the case, and indicates the
es the highlighted scenario and adds a new scenario to
Removes the currently highlighted scenario. There must
rent one, highlight the appropriate
Adding/Editing Scenariosprogrammed limits on the number of
Scenarios list, and
18
General TabYou may provide the following information on the
Fig 3.3
Data
Name
System Back Pres
General TabYou may provide the following information on the General tab:
Description
An alphanumeric description of the scenario (e.g. PowerFailure).
System Back Pres. The system back pressure at the Flare Tip exit. Thinormally be atmospheric pressure, but can be set to representsystem design conditions at the exit point. If left empty, thevalue on the Calculation Options Editor will be used. Theminimum value is 0.01 bar (absolute pressure).
3 Scenarios
tab:
An alphanumeric description of the scenario (e.g. Power
ip exit. This willnormally be atmospheric pressure, but can be set to representsystem design conditions at the exit point. If left empty, the
will be used. Theminimum value is 0.01 bar (absolute pressure).
3 Scenarios
Constraints TabThis tab requires the following information for both headers and tailpipes.
Fig 3.4
Tailpipes are indicated by thePipe Editor. You may provide different design information (Noise at 1 m, Vapor VelTailpipes. Any boxes may be left empty, in which case they will be ignored.
Data
Mach Number
Vapor Velocity
Liquid Velocity
Constraints Tabis tab requires the following information for both headers and tailpipes.
Tailpipes are indicated by the Tailpipe field on the Connections. You may provide different design information (Mach Number
Vapor Velocity, Liquid Velocity) for the Headers. Any boxes may be left empty, in which case they will be ignored.
Description
The maximum allowable Mach number for all pipe segments.Calculated values that exceed this number will be highlighted in theresults.
The maximum allowable vapor velocity. Calculated velocities thatexceed this value will be indicated in the results.
The maximum allowable liquid velocity. Calculated velocities thatexceed this value will be indicated in the results.
19
is tab requires the following information for both headers and tailpipes.
Connections box of theMach Number,
Headers and. Any boxes may be left empty, in which case they will be ignored.
The maximum allowable Mach number for all pipe segments.e highlighted in the
The maximum allowable vapor velocity. Calculated velocities that
The maximum allowable liquid velocity. Calculated velocities that
20 3 Scenarios
Rho V2 The density times the velocity square. This value is normally usedas a limiting factor to prevent erosion.
Noise The maximum allowable sound pressure level at a distance of 1meter for all pipe segments. This is an average value over thelength of the pipe. Calculated values that exceed this specificationwill be highlighted in the results.
Check Vel.Constraint
Specify either Mixture Velocity or Phase Superficial Velocity isused while checking the velocity constraints for design in ascenario.
Note: Whilst rating the network you may define a Mach number constraint of1.00, in order to highlight only choked flow conditions. This is notrecommended for design calculations where a more reasonable value such as0.5 or 0.7 will lead to a more rapid solution towards the maximum allowableback pressure constraints.
Sources TabIf a source is ignored, the MABP constraint is ignored by sizing calculations.
When you select the Sources tab, you will see that all sources are displayedon this tab.
Note: If you are setting up a new case, the Sources tab will not show anysources.
3 Scenarios
Fig 3.5
This tab is useful in that you can easily toggle whether or not individualsources are to be included in the current scenario,unnecessarily delete sources or set the flow of a source to zero.
Estimates TabThe Estimates tab allows some control over the selection and initialization offlowrates for pipes which are to be used as tears in the solution of loosystems. The use to which each field is put is dependent upon theAnalyzer setting on the
The check boxes in thepipes from being used as tearsbeing used as a tear or clear it to allow it. This setting has no effect if theSimultaneous structural analyzer is used.
When the Convergentrecommends a tear locatiIf the structural analyzer does find that the pipe may be a valid tear locationthen this value is ignored.
This tab is useful in that you can easily toggle whether or not individualsources are to be included in the current scenario, without having to eitherunnecessarily delete sources or set the flow of a source to zero.
Estimates Tabtab allows some control over the selection and initialization of
flowrates for pipes which are to be used as tears in the solution of loosystems. The use to which each field is put is dependent upon the
setting on the Solver tab of Calculation Options Editor
The check boxes in the No Tear column of the table allow you to preventpipes from being used as tears - select the check box to prevent a pipe frombeing used as a tear or clear it to allow it. This setting has no effect if the
structural analyzer is used.
Convergent structural analyzer is used, the Molar Flowrecommends a tear location and initial value for the flow at the tear location.If the structural analyzer does find that the pipe may be a valid tear locationthen this value is ignored.
21
This tab is useful in that you can easily toggle whether or not individualwithout having to either
unnecessarily delete sources or set the flow of a source to zero.
tab allows some control over the selection and initialization offlowrates for pipes which are to be used as tears in the solution of loopedsystems. The use to which each field is put is dependent upon the Structure
Calculation Options Editor.
column of the table allow you to preventt the check box to prevent a pipe from
being used as a tear or clear it to allow it. This setting has no effect if the
Molar Flow columnon and initial value for the flow at the tear location.
If the structural analyzer does find that the pipe may be a valid tear location,
22
When the Simultaneousis used to seed thlong as the structural analysis succeeds but the pipe will not necessarily beselected as a tear pipe. In the event that the structural analysis fails with anyMolar Flow estimates
Fig 3.6
Since the Simultaneousperformance than thespecify information on theimproving the speed of convergence of the model. In the event that a modelproves problematic to converge, a number of additional columns are availableto tune the convergence algorithms. These may be exposed by stretching theview horizontally.
The Max. Step column defines the maximum change to the flow in a tearpipe over a single iteration whilst theconstrain the flow in a tear pipe. Not all these values are used by all theSolver algorithms.
Simultaneous structural analyzer is used, the Molar Flowis used to seed the analyzer. This value will always impact the initialization aslong as the structural analysis succeeds but the pipe will not necessarily beselected as a tear pipe. In the event that the structural analysis fails with any
estimates, the model will be initialized by the default values.
Simultaneous structural analyzer generally offers betterperformance than the Convergent analyzer it will rarely be necessary tospecify information on the Estimates tab other than for the purimproving the speed of convergence of the model. In the event that a modelproves problematic to converge, a number of additional columns are availableto tune the convergence algorithms. These may be exposed by stretching theview horizontally.
column defines the maximum change to the flow in a tearpipe over a single iteration whilst the Max. Flow and Min. Flowconstrain the flow in a tear pipe. Not all these values are used by all the
algorithms.
3 Scenarios
Molar Flow columne analyzer. This value will always impact the initialization as
long as the structural analysis succeeds but the pipe will not necessarily beselected as a tear pipe. In the event that the structural analysis fails with any
will be initialized by the default values.
structural analyzer generally offers betteranalyzer it will rarely be necessary to
tab other than for the purpose ofimproving the speed of convergence of the model. In the event that a modelproves problematic to converge, a number of additional columns are availableto tune the convergence algorithms. These may be exposed by stretching the
column defines the maximum change to the flow in a tearMin. Flow columns
constrain the flow in a tear pipe. Not all these values are used by all the Loop
3 Scenarios 23
Max. Step Max. Flow Min. Flow
Newton-Raphson 3 3 3
Broyden 3 3 3
Force Convergent
Conjugate Gradient Minimisation
Quasi-Newton Minimization
Scenario ToolsThe complete analysis of a flare system should ideally include analysis of thesystem for the scenarios in which each source relieves on its own. For a largenetwork with many sources, it can become tedious to define each of thesescenarios. These can automatically be added to your model as follows.
Adding Single Source ScenariosClick Source Tools from the Tools group on the Home tab of the Ribbon,then select Add Single Source Scenarios or use the hot key combinationAlt, H, U, A. Click OK for the message that pops up.
This will analyze your model and add a scenario for each source that has anon-zero flow rate defined in at least one scenario. Source data will be copiedfrom the scenario in which it has the highest flow rate.
24 3 Scenarios
4 Pipe Network 25
4 Pipe Network
This section provides information on the following topics:
Overview
Pipe Manager
Ignoring/Restoring Pipes
Multiple Editing
OverviewThe pipe network comprises a series of interconnected pipes. These pipes canbe added, edited and deleted from the Pipe Manager.
Pipe ManagerTo access the Pipe Manager, click Pipes in the Build group on the Hometab of the Ribbon.
26
Fig 4.1
The following buttons are available:
Button Description
Add Adds a new pipe segment. This new pipe will be named with a numberdepending upon the number of pipes already ad
Edit Edits the currently highlighted pipe segment.
Delete Removes the currently highlighted pipe segment.
Close Closes the
Ignoring/Restoring PipesWhen you ignore a single pipe, all upstream pipes are automatically ignored.
You can ignore single or multiple pipes within the model. When you ignore asingle pipe, all upstream nodes are automatically ignored. This enables you todo what if type calculations, where part of the network can be excluded fromthe calculation without the needappropriate nodes.
To ignore a pipe:
1 Open the Pipe Editor
2 On the Connections
The following buttons are available:
Description
Adds a new pipe segment. This new pipe will be named with a numberdepending upon the number of pipes already added.
Edits the currently highlighted pipe segment.
Removes the currently highlighted pipe segment.
Closes the Pipe Manager.
Ignoring/Restoring PipesWhen you ignore a single pipe, all upstream pipes are automatically ignored.
ignore single or multiple pipes within the model. When you ignore asingle pipe, all upstream nodes are automatically ignored. This enables you to
type calculations, where part of the network can be excluded fromthe calculation without the need for deletion and reinstallation of theappropriate nodes.
To ignore a pipe:
Pipe Editor window of the pipe that you want to ignore.
Connections tab, select the Ignore check box.
4 Pipe Network
Adds a new pipe segment. This new pipe will be named with a number
Ignoring/Restoring PipesWhen you ignore a single pipe, all upstream pipes are automatically ignored.
ignore single or multiple pipes within the model. When you ignore asingle pipe, all upstream nodes are automatically ignored. This enables you to
type calculations, where part of the network can be excluded fromfor deletion and reinstallation of the
window of the pipe that you want to ignore.
4 Pipe Network 27
Fig 4.2
To restore a pipe that has previously been ignored:
1 Open the Pipe Editor window of the pipe that you want to restore.
2 On the Connections tab, clear the Ignore check box.
Connections TabThe name of the pipe segment and connectivity information is specified here.
28
Fig 4.3
The following fields are available on this tab:
Input Data Description
Name An alphanumeric description of the pipe segment.
Location An alphanusegment.
UpstreamNode
This is the name of the node upstream of the pipe. The list allowsyou to select from a list of existing unconnected nodes in the model.
DownstreamNode
This is the nameyou to select from a list of existing unconnected nodes in the model.
Tailpipe This list allows you to select whether the pipe should be treated as atailpipe. If set tooption is selected in thepressure drop for this pipe will be calculated using the rated flow inplace of the relieving flow rate.
Ignore This checkcalculationnodes and pipes will be ignored during calculations.
Fitting Loss The fitting loss for the pipe segment. You cannot change the valueshown in this box. Instead, calculated value on thebe updated by clicking
The following fields are available on this tab:
Description
An alphanumeric description of the pipe segment.
An alphanumeric description of the location within the plant for thesegment.
This is the name of the node upstream of the pipe. The list allowsyou to select from a list of existing unconnected nodes in the model.
This is the name of the node upstream of the pipe. The list allowsyou to select from a list of existing unconnected nodes in the model.
This list allows you to select whether the pipe should be treated as atailpipe. If set to Yes and the Rated Flow for Tailpipoption is selected in the Calculation Options dialog box, thepressure drop for this pipe will be calculated using the rated flow inplace of the relieving flow rate.
This check box may be selected to remove the pipe fromcalculations temporarily. When selected the pipe and all upstreamnodes and pipes will be ignored during calculations.
The fitting loss for the pipe segment. You cannot change the valueshown in this box. Instead, calculated value on thebe updated by clicking Link or Paste.
4 Pipe Network
meric description of the location within the plant for the
This is the name of the node upstream of the pipe. The list allowsyou to select from a list of existing unconnected nodes in the model.
of the node upstream of the pipe. The list allowsyou to select from a list of existing unconnected nodes in the model.
This list allows you to select whether the pipe should be treated as aRated Flow for Tailpipes calculation
dialog box, thepressure drop for this pipe will be calculated using the rated flow in
box may be selected to remove the pipe froms temporarily. When selected the pipe and all upstream
nodes and pipes will be ignored during calculations.
The fitting loss for the pipe segment. You cannot change the valueshown in this box. Instead, calculated value on the Fittings tab can
4 Pipe Network
You have the option of modeling a pipe segment as a main header or atailpipe. The ability to classify a pipe as either a tailpipe or a header allowsyou to perform calculations in which the pressure drop for tailpidetermined by the rated flow and that for headers is determined by thenominal flow. This is in accordance with API
In the Scenario EditorVapor and Liquid Velocitiesheaders and the tailpipes.
Dimensions TabThe physical dimensions and characteristics of the pipe segment are specifiedhere.
Fig 4.4
The following fields are available on this tab:
Input Data
Length
You have the option of modeling a pipe segment as a main header or atailpipe. The ability to classify a pipe as either a tailpipe or a header allowsyou to perform calculations in which the pressure drop for tailpidetermined by the rated flow and that for headers is determined by thenominal flow. This is in accordance with API-RP-521.
Scenario Editor, you can set design limits for the Mach NumberLiquid Velocities, Rho V2 and Noise separately for the main
headers and the tailpipes.
Dimensions TabThe physical dimensions and characteristics of the pipe segment are specified
The following fields are available on this tab:
Description
The physical length of the pipe segment. This length is used inassociation with the fittings loss coefficients to calculate theequivalent length of the pipe. If you have equivalent length datafor your network, enter this data here as the sum of the actual
29
You have the option of modeling a pipe segment as a main header or atailpipe. The ability to classify a pipe as either a tailpipe or a header allowsyou to perform calculations in which the pressure drop for tailpipes isdetermined by the rated flow and that for headers is determined by the
Mach Number,ly for the main
The physical dimensions and characteristics of the pipe segment are specified
the pipe segment. This length is used inassociation with the fittings loss coefficients to calculate theequivalent length of the pipe. If you have equivalent length datafor your network, enter this data here as the sum of the actual
30 4 Pipe Network
Input Data Description
length plus the equivalent length of the fittings and enter zero forthe fittings loss coefficients.
Elevation Change A positive elevation indicates that the outlet is higher than theinlet.
Material The pipe material, either Carbon Steel or Stainless Steel.
Roughness The surface roughness of the pipe segment. Whenever a materialis selected, the absolute roughness is initialized to the defaultvalue for the material as defined on the Preferences view.
ThermalConductivity
The thermal conductivity of the pipe wall. This is used by theheat transfer calculations when these are enabled.
NominalDiameter
The nominal pipe diameter used to describe the pipe size. Forpipes with a nominal diameter of 14 inches or more, this will bethe same as the outside diameter of the pipe.
Schedule Select a schedule number from the list, you will be able to selecta nominal pipe diameter from the pipe databases. It will not benecessary to specify the Internal Diameter or the WallThickness for the pipe.
InternalDiameter
The pipe diameter used for the pressure drop calculations.
Wall Thickness The thickness of the pipe wall. Valid values are any positivenumber or zero.
Use Class Select Yes to restrict the pipe sizes to those defined by the PipeClass.
Sizeable If you wish the pipe segment to be resized by sizing calculations,Yes should be selected. For example, a model of a networkcontaining a representation of the knockout drum, as a pipesegment would normally leave this unchecked such that sizingcalculations for the pipes would not change the knockout drumsize.
Schedule Numbers
Carbon Steel:
10, 20, 30, 40, 60, 80, 100, 120, 140, 160, STD, XS, XXS, User
Stainless Steel:
5S, 10S, 40S, 80S
Fittings TabA list of pipe fittings may be added to the pipe segment. These fittings will bemodeled as an additional equivalent length applied linearly over the physicallength of the pipe segment.
4 Pipe Network
Fig 4.5
The following fields are available on this tab:
Input Data
LengthMultiplier
Fittings Loss
From the Database Fittingthen click Add to mselect as many fittings as required. The final fitting loss equation, which willbe a sum of all the selected fittings, will appear in a display field underneaththe Selected Fitting
Click Link to transfer the coefficients for this equation into thefield on the Connections
Click Paste to transfer the coefficients for the fitting equation into theFittings Loss field
To remove the selected fitting individually, select the fitting and click
The following fields are available on this tab:
Description
The length of the pipe is multiplied by this value to determine theequivalent length used for the pressure drop calculation. If leftblank then the value on the Calculation Options EditorThis option is useful for making an allowance for bends and otherfittings if these are not known.
The fittings "K" factor is calculated from the following equation inwhich Ft is the friction factor for fully developed turbulent flow:
K = A + BFt
Database Fittings list, select the appropriate type of fitting, andto move the selection to the Selected Fittings
select as many fittings as required. The final fitting loss equation, which willbe a sum of all the selected fittings, will appear in a display field underneath
Selected Fittings list.
to transfer the coefficients for this equation into theConnections tab, while maintaining the list of fittings.
to transfer the coefficients for the fitting equation into thefield. The selected list of fittings will not be retained.
To remove the selected fitting individually, select the fitting and click
31
ue to determine theequivalent length used for the pressure drop calculation. If left
Calculation Options Editor is used.This option is useful for making an allowance for bends and other
The fittings "K" factor is calculated from the following equation inis the friction factor for fully developed turbulent flow:
list, select the appropriate type of fitting, ands list. You can
select as many fittings as required. The final fitting loss equation, which willbe a sum of all the selected fittings, will appear in a display field underneath
to transfer the coefficients for this equation into the Fittings Loss, while maintaining the list of fittings.
to transfer the coefficients for the fitting equation into theof fittings will not be retained.
To remove the selected fitting individually, select the fitting and click Delete.
32
Note: The network cannot be sized correctly if you specify equivalent lengthdata to model fittings losses, since the equivalent length of aa function of the pipe diameter and will therefore be incorrect when thediameters change.
Heat Transfer TabThe pipe segment may perform calculations taking into account heat transferwith the external air.
Fig 4.6
The following field
Input Data
External Conditions Group
External Medium
Temperature
The network cannot be sized correctly if you specify equivalent lengthdata to model fittings losses, since the equivalent length of any pipe fitting isa function of the pipe diameter and will therefore be incorrect when thediameters change.
Heat Transfer TabThe pipe segment may perform calculations taking into account heat transferwith the external air.
The following fields are available on this tab:
Description
External Conditions Group
Select the external medium. Two options arecurrently available: Air or Sea Water
Enter the temperature of the external air. If this fieldis left blank, the global value set via theOptions Editor is used.
4 Pipe Network
The network cannot be sized correctly if you specify equivalent lengthny pipe fitting is
a function of the pipe diameter and will therefore be incorrect when the
The pipe segment may perform calculations taking into account heat transfer
Select the external medium. Two options areSea Water.
Enter the temperature of the external air. If this fieldthe global value set via the Calculation
4 Pipe Network 33
Input Data Description
External Medium Velocity Enter the velocity of the external medium. If this fieldis left blank, the global value set via the CalculationOptions Editor is used.
Heat Transfer Enabled This list selects whether heat transfer calculations areto be performed for the pipe. Furthermore, settingonly enables heat transfer calculations if the EnableHeat Transfer option is also selected in theCalculation Options Editor.
External Radiative HTC This list selects whether or not the external radiativeheat transfer coefficient is included within the heattransfer calculations.
Emissivity Enter the fractional Emissivity to be used forradiative heat transfer calculations.
Multiple Element Calculation This list selects whether the heat transfer calculationis done using a single element or the same number ofelements as the pressure drop calculation. If Yes isselected, the heat transfer calculation sues the samenumber of elements as the pressure drop calculation
Insulation Group
Description A brief description to identify the type of pipeinsulation.
Thickness Supply the insulation thickness.
Thermal Conductivity Enter the insulation thermal conductivity.
Heating Group
Outlet Temp You can explicitly set an outlet temperature for thissegment, or leave it blank. A heater in a flareknockout drum is an example of process equipmentthat may require a fixed outlet temperature.
Duty Enter the heating duty and the outlet temperaturewill be calculated based on the inlet temperature andthe defined duty.
Methods TabCalculation methods are specified here.
34
Fig 4.7
The following fields are available on this tab:
Input Field Description
VLE Method Group
VLE Method The options for the Vafollows (see
The following fields are available on this tab:
Description
VLE Method Group
The options for the Vapor-Liquid Equilibrium calculations are asfollows (see Chapter 9 Theoretical Basis for more details):
Compressible Gas - Real Gas relationship. This is onlyavailable when the Enthalpy Method on theOptions Editor is Ideal Gas.
Peng Robinson - Peng Robinson Equation of Stateavailable when the Enthalpy Method on theOptions Editor is NOT Ideal Gas.
Soave Redlich Kwong - Soave Redlich Kwong Equation ofState. This is available when the Enthalpy MethodCalculation Options Editor is NOT Ideal Gas
Vapor Pressure - Vapor Pressure method as described in APITechnical Data Book Volume 113. This is available when theEnthalpy Method on the Calculation Options EditorNOT Ideal Gas.
Model Default - If this is selected, the Default method for theVLE method (as defined on the Calculation Options Editorwill be used.
4 Pipe Network
Liquid Equilibrium calculations are asfor more details):
This is onlyon the Calculation
Peng Robinson Equation of State. This ison the Calculation
Soave Redlich Kwong Equation ofEnthalpy Method on the
Ideal Gas.
Vapor Pressure method as described in APIThis is available when the
Calculation Options Editor is
If this is selected, the Default method for theCalculation Options Editor)
4 Pipe Network 35
Input Field Description
Pressure Drop Group
Horizontaland InclinedPipes
The Horizontal/Inclined methods apply only when you haveselected Two-Phase pressure drop. The options are:
Isothermal Gas - This is a compressible gas method thatassumes isothermal expansion of the gas as it passes alongthe pipe. Aspen Flare System Analyzer uses averagedproperties of the fluid over the length of the pipe. The outlettemperature from the pipe is calculated by adiabatic heatbalance either with or without heat transfer. Pressure lossesdue to change in elevation are ignored.
Adiabatic Gas - This is a compressible gas method thatassumes adiabatic expansion of the gas as it passes along thepipe. As with the Isothermal Gas method, pressure losses dueto changes in elevation are ignored.
Beggs & Brill - The Beggs and Brill method is based on workdone with an air-water mixture at many different conditions,and is applicable for inclined flow.
Dukler - Dukler breaks the pressure drop in two-phasesystems into three components - friction, elevation andacceleration. Each component is evaluated independently andadded algebraically to determine the overall pressure drop.
Lockhart Martinelli – Lockhart Martinelli correlations modelsthe two phase pressure drop in terms of a single phasepressure drop multiplied by a correction factor. Accelerationchanges are not included.
Beggs and Brill (No Acc.) – The Beggs and Brill methodswithout the acceleration term.
Beggs and Brill (Homog.) – The Beggs and Brill methods witha homogeneous acceleration term.
Dukler (AGA Head) - Uses the AGA equation for thecalculation of the static head term rather than the Eatonequation which can be poor when you have small quantities ofliquid in the system.
Model Default - If this is selected, the Default method for theHorizontal/Inclined method (as defined on the CalculationOptions Editor) will be used.
36 4 Pipe Network
Input Field Description
VerticalPipes
The Vertical method applies only when you have selected Two-Phasepressure drop. The options are:
Isothermal Gas - This is a compressible gas method thatassumes isothermal expansion of the gas as it passes alongthe pipe. Aspen Flare System Analyzer uses averagedproperties of the fluid over the length of the pipe. The outlettemperature from the pipe is calculated by adiabatic heatbalance either with or without heat transfer. Pressure lossesdue to change in elevation are ignored.
Adiabatic Gas - This is a compressible gas method thatassumes adiabatic expansion of the gas as it passes along thepipe. As with the Isothermal Gas method, pressure losses dueto changes in elevation are ignored.
Beggs & Brill - Although the Beggs and Brill method was notoriginally intended for use with vertical pipes, it isnevertheless commonly used for this purpose, and istherefore included as an option for vertical pressure dropmethods. For more details, see Chapter 9 Theoretical Basis.
Dukler - Although the Dukler method is not generallyapplicable to vertical pipes, it is included here to allowcomparison with the other methods.
Orkiszewski - This is a pressure drop correlation for vertical,two-phase flow for four different flow regimes - bubble, slug,annular-slug transition and annular mist. For more details,see Appendix A - Theoretical Basis.
Lockhart Martinelli – Lockhart Martinelli correlations modelsthe two phase pressure drop in terms of a single phasepressure drop multiplied by a correction factor. Accelerationchanges are not included.
Beggs and Brill (No Acc.) – The Beggs and Brill methodswithout the acceleration term.
Beggs and Brill (Homog.) – The Beggs and Brill methods witha homogeneous acceleration term.
Model Default - If this is selected, the Default method for theVertical method (as defined on the Calculation OptionsEditor) will be used.
Elements For two-phase calculations, the pipe segment is divided into aspecified number of elements. On each element, energy and materialbalances are solved along with the pressure drop correlation. Insimulations involving high heat transfer rates, many increments maybe necessary, due to the non-linearity of the temperature profile.Obviously, as the number of increments increases, so does thecalculation time; therefore, you should try to select a number ofincrements that reflects the required accuracy.
4 Pipe Network 37
Input Field Description
FrictionFactorMethod
The Friction Factor Method applies only when you have entered avalue for friction factor. The options are:
Round - This method has been maintained primarily forhistorical purposes in order for older Aspen Flare SystemAnalyzer calculations to be matched. It tends to over predictthe friction factor by up to 10% in the fully turbulent region.
Chen - It should always be the method of preference since itgives better predictions at the fully turbulent flow conditionsnormally found within flare systems.
Model Default - If this is selected, the Default method for theFriction Factor Method (as defined on the CalculationOptions Editor) will be used.
Static HeadContribution
The following options are available:
Include - The static head contribution to total pressure drop inthe pipe segments is included.
Ignore Downhill Recovery - The static head recovery term isignored for downhill sections of pipe.
Ignore - The static head contribution to the pressure dropcalculation for all pipe segments is ignored.
Include is applied by default.
Solver Group
DampingFactor
The damping factor used in the iterative solution procedure. If this isleft blank, the value in the Calculation Options Editor is used.
Note: When you are sizing a flare system, the initial pipe diameters mayaffect the solution when there is a liquid phase and the liquid knockout drumis modeled. You should initially size a network using vapor phase methods.
Summary TabThe results of the calculation are displayed.
38
Fig 4.8
Multiple EditingYou can edit multiple pipe segments simultaneouslthe Pipe Managerpressed. After you have finished selecting pipe segments, clickthe common Pipe Editor
The common pipe editor view differs from that of the single pin the following respects:
Only fields that can be edited in multiple mode are displayed.
The input fieldsthat the value should remain at the pre edit value.
In the following figure of theLengthnot be changed. We specify new values for thethe Thermal ConductivitySizeable
Multiple EditingYou can edit multiple pipe segments simultaneously by highlighting them in
Pipe Manager with the mouse cursor while keeping the Spressed. After you have finished selecting pipe segments, click
Pipe Editor.
The common pipe editor view differs from that of the single pipe editor viewin the following respects:
Only fields that can be edited in multiple mode are displayed.
The input fields have an additional entry, *. This entry indicatesthat the value should remain at the pre edit value.
In the following figure of the Dimensions tab; we enter * for theLength and Elevation Change fields to indicate that these mustnot be changed. We specify new values for the Roughness
Thermal Conductivity. We select * for the Use ClassSizeable boxes to indicate that these must be changed.
4 Pipe Network
y by highlighting them inShift key
pressed. After you have finished selecting pipe segments, click Edit to open
ipe editor view
Only fields that can be edited in multiple mode are displayed.
have an additional entry, *. This entry indicates
tab; we enter * for thefields to indicate that these must
Roughness andUse Class and
must be changed.
4 Pipe Network
Fig 4.9
Pipe Class EditorThe Pipe Class Editornominal diameter, for bothcalculations. It also allows you to restrict the range of pipe sizes that may beselected during design calculations.
To access the Pipe Class Editortab.
Pipe Class EditorPipe Class Editor allows you to edit the allowable schedules for each
nominal diameter, for both Carbon Steel and Stainless Steels. It also allows you to restrict the range of pipe sizes that may be
selected during design calculations.
Pipe Class Editor, click Pipe Class in Tools, on the
39
allows you to edit the allowable schedules for eachStainless Steel, during sizing
s. It also allows you to restrict the range of pipe sizes that may be
, on the Home
40 4 Pipe Network
Fig 4.10
Note: If you have selected Use Pipe Class in the Preference Editor, theseare the schedules which will be used.
5 Nodes 41
5 Nodes
This section provides information on the following topics:
Overview
Node Manager
Ignoring/Restoring Nodes
Connection Nodes
Boundary Nodes
OverviewPipes are connected via nodes, which can be added, edited and deleted fromthe Node Manager. Sources are also added through the Node Manager.
Node ManagerTo access the Node Manager:
Click Nodes in Build, on the Home tab.
42
Fig 5.1
The following buttons are available:
Button Description
Add You will be prompted to select the type of node. This new node will benamed with a number depending upon the number of nodes of thattype already added.
Edit Allows you to edit the currently highlighted node. The form varies,depending
Delete Allows you to remove the currently highlighted node.
Close Closes the
Ignoring/Restoring NodesWhen you ignore a single node, all upstream nodes are automatically ignored.
You can ignore sinsingle node, all upstream nodes are automatically ignored. This enables youto do what if type calculations, where part of the network can be excludedfrom the calculation without the need for deletappropriate nodes.
To ignore a node
1 Open the node editor
2 On the Connectionsfigure shows this for a connector node
The following buttons are available:
Description
You will be prompted to select the type of node. This new node will benamed with a number depending upon the number of nodes of thattype already added.
Allows you to edit the currently highlighted node. The form varies,depending on the type of node, as discussed below.
Allows you to remove the currently highlighted node.
Closes the Node Manager.
Ignoring/Restoring NodesWhen you ignore a single node, all upstream nodes are automatically ignored.
You can ignore single or multiple nodes within the model. When you ignore asingle node, all upstream nodes are automatically ignored. This enables you
type calculations, where part of the network can be excludedfrom the calculation without the need for deletion and reinstallation of theappropriate nodes.
To ignore a node:
Open the node editor of the node that you want to ignore.
Connections tab, select the Ignore check box. The fofigure shows this for a connector node.
5 Nodes
You will be prompted to select the type of node. This new node will benamed with a number depending upon the number of nodes of that
Allows you to edit the currently highlighted node. The form varies,
Ignoring/Restoring NodesWhen you ignore a single node, all upstream nodes are automatically ignored.
gle or multiple nodes within the model. When you ignore asingle node, all upstream nodes are automatically ignored. This enables you
type calculations, where part of the network can be excludedion and reinstallation of the
box. The following
5 Nodes 43
Fig 5.2
To restore a node that has previously been ignored:
1 Open the node editor of the node that you want to restore.
2 On the Connections tab, clear the Ignore check box.
Connection NodesThe following types of connection nodes are available in Aspen Flare SystemAnalyzer. A connection node is one that links two or more pipe segments.
Connector
Flow Bleed
Horizontal Separator
Orifice Plate
Tee
Vertical Separator
ConnectorThe Connector is used to model the connection of two pipes. The diametersof the pipes may be different.
44
Connections Tab
The name of the connector and connectivity information is
Fig 5.3
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available
Field Description
Name The alphanumeric description of the1).
Location You may want to specify the location of the node in the plant.
Upstream/Downstream
Either type in the name of the pipe segment or select
At You can specify the end of the pipe segment attached to theconnector.
Ignore Select thecalculations. Clear the check
Calculations Tab
Calculation methods are spec
Connections Tab
The name of the connector and connectivity information is specified here.
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Description
The alphanumeric description of the Connector (e.g.1).
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select
You can specify the end of the pipe segment attached to theconnector.
Select the Ignore check box to ignore this connector in thecalculations. Clear the check box to re-enable it.
Calculations Tab
Calculation methods are specified here.
5 Nodes
specified here.
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to different
(e.g. - HP Connect
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select from the list.
You can specify the end of the pipe segment attached to the
box to ignore this connector in the
5 Nodes
Fig 5.4
The following fields are available on this tab:
Field Description
Angle Specify the connector expansion angle. If not defined, it will becalculated
Length Enter the connector length. If not defined, it will be calculaAngle
Fitting LossMethod
The available options are:
IsothermalPressure Drop
If this option is set tochange calculations in the connector will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to updatethe inlet properties. If the option isflash will be used to update the inlet properties.
The connector will do one size change calculation between the inletand outlet diameters selecting expansion or contraction asappropriate.
Setting this option toat cost of a minor loss of accuracy.
Two PhaseCorrection
If this option is set toflow will be calculated using properties corrected for liquid slip. If settocalculating the pressure loss coefficient.
The following fields are available on this tab:
Description
Specify the connector expansion angle. If not defined, it will becalculated from Length.
Enter the connector length. If not defined, it will be calculaAngle.
The available options are:
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Calculated – Pressure drop is calculated in accordance withthe Swage method.
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the connector will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to updatethe inlet properties. If the option is set to No, a more rigorous PHflash will be used to update the inlet properties.
The connector will do one size change calculation between the inletand outlet diameters selecting expansion or contraction asappropriate.
Setting this option to Yes can speed up calculations in some casesat cost of a minor loss of accuracy.
If this option is set to Yes, the pressure loss coefficient in two phaseflow will be calculated using properties corrected for liquid slip. If setto No, the homogenous properties of the fluid will be used incalculating the pressure loss coefficient.
45
Specify the connector expansion angle. If not defined, it will be
Enter the connector length. If not defined, it will be calculated from
Pressure drop calculation is ignored
Pressure drop is calculated in accordance with
, the inlet temperatures used for the sizechange calculations in the connector will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to update
a more rigorous PH
The connector will do one size change calculation between the inletand outlet diameters selecting expansion or contraction as
ed up calculations in some cases
the pressure loss coefficient in two phaseflow will be calculated using properties corrected for liquid slip. If set
enous properties of the fluid will be used in
46 5 Nodes
Field Description
SwageMethod
The following options are available:
Compressible - pressure losses will be calculated assumingcompressible flow through the connector at all times.
Incompressible (Crane) - pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using Cranecoefficients.
Transition - pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressibleflow method.
Incompressible (HTFS) - pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using HTFScorrelations
The Incompressible method calculations are faster but will beless accurate at higher pressure drops. The Transition methodcan cause instabilities in some cases if the calculated pressuredrop is close to the transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
5 Nodes
Fig 5.5
Flow BleedThe Flow Bleed is a simple calculation block that allows you to;
Specify a fixed pressure drop
Specify a constrained flow offtake whfrom the following equation
Offtake = Multiplier x Inlet Flow + Offset
The calculated Offtake is constrained to maximum and minimum values.
Connections Tab
The name of the flow bleed and connectivity information is speci
Flow BleedThe Flow Bleed is a simple calculation block that allows you to;
Specify a fixed pressure drop.
Specify a constrained flow offtake where the flow offtake is calculatedfrom the following equation:
Offtake = Multiplier x Inlet Flow + Offset
The calculated Offtake is constrained to maximum and minimum values.
Connections Tab
The name of the flow bleed and connectivity information is speci
47
The Flow Bleed is a simple calculation block that allows you to;
ere the flow offtake is calculated
The calculated Offtake is constrained to maximum and minimum values.
The name of the flow bleed and connectivity information is specified here.
48
Fig 5.6
The following fields are available on this tab:
Field Description
Name The alphanumeric description of theXX).
Location You may want to specify the location of the
Upstream/Downstream
Either type in the name of the pipe segment or select from the list.
At You can specify the end of the pipe segment attached to theb
Ignore Select thecalculations. Clear the check
Calculations Tab
Calculation methods are specified here.
The following fields are available on this tab:
Description
The alphanumeric description of the Flow Bleed (e.g.XX).
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select from the list.
You can specify the end of the pipe segment attached to thebleed.
Select the Ignore check box to ignore this flow bleed in thecalculations. Clear the check box to re-enable it.
Calculations Tab
Calculation methods are specified here.
5 Nodes
(e.g. - HP Connect
in the plant.
Either type in the name of the pipe segment or select from the list.
You can specify the end of the pipe segment attached to the flow
box to ignore this flow bleed in the
5 Nodes
Fig 5.7
The following fields are available on this tab:
Field
Offtake Multiplier
Offtake Offset
Offtake Minimum
OfftakeMaximum
Pressure Drop
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
The following fields are available on this tab:
Description
Specify the Offtake multiplier. The default value is 0.
Specify the Offset for the Offtake to compensate for the changesin the inlet flow.
Specify the minimum value for the Offtake.
Specify the maximum value for the Offtake.
Enter the pressure drop across the Flow Bleed.
ry Tab
The result of the calculations at each of the pipe connections is displayed.
49
Specify the Offtake multiplier. The default value is 0.
et for the Offtake to compensate for the changes
The result of the calculations at each of the pipe connections is displayed.
50
Fig 5.8
Horizontal SeparatorHorizontal separators are used to allow liquid to separate from the feedstream so that it can be removed from the flare system. The liquid phase inthe horizontal separatorSystem Analyzer, thesecondary inlet/outlet, and one vapor outl
Connections Tab
The name of the horizontal separator and connectivity information is specifiedhere.
Horizontal Separatoreparators are used to allow liquid to separate from the feed
m so that it can be removed from the flare system. The liquid phase ineparator feed is removed from the network. In Aspen Flare
System Analyzer, the Horizontal Separator has one primary inlet, onesecondary inlet/outlet, and one vapor outlet stream.
Connections Tab
The name of the horizontal separator and connectivity information is specified
5 Nodes
eparators are used to allow liquid to separate from the feedm so that it can be removed from the flare system. The liquid phase in
feed is removed from the network. In Aspen Flarehas one primary inlet, one
The name of the horizontal separator and connectivity information is specified
5 Nodes
Fig 5.9
You only need to provide 2 of 3 connections to be able to solve the separator.This allows for solution(s) to partially built network
The following fields are available on this tab:
Field
Name
Location
(Primary/Secondary)Inlet/Outlet
At
Ignore
Calculations Tab
Calculation methods are specified here.
You only need to provide 2 of 3 connections to be able to solve the separator.This allows for solution(s) to partially built networks.
The following fields are available on this tab:
Description
The alphanumeric description of the Horizontal Separator(e.g. - HP KO Drum).
You may want to specify the location of the nodeThe location can have an alphanumeric name. This feature isuseful for large flowsheets, because you can provide a different“location” name to different sections to make it morecomprehensible.
Either type in the name of the pipe segment or selectlist.
You can specify the end of the pipe segment attached to thehorizontal separator.
Select the Ignore check box to ignore this horizontal separatorin the calculations. Clear the check box to re-enable it.
Calculations Tab
tion methods are specified here.
51
You only need to provide 2 of 3 connections to be able to solve the separator.
Horizontal Separator
node in the plant.hanumeric name. This feature is
useful for large flowsheets, because you can provide a different“location” name to different sections to make it more
Either type in the name of the pipe segment or select from the
You can specify the end of the pipe segment attached to the
box to ignore this horizontal separatorenable it.
52
Fig 5.10
The following fields are available on this tab:
Field
Dimensions Group
Diameter
Liquid Level
Methods Group
Fitting LossMethod
The following fields are available on this tab:
Description
Dimensions Group
The internal diameter of the vessel.
The liquid level in the vessel. Pressure drop is calculated basedupon the vapor space above the liquid.
The available options are;
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Calculated_Ignore Vena Contracta – Pressure drop iscalculated in accordance with the Swageignores the loss due vena contracta.
Calculated – Pressure drop is calculated in accordance withthe Swage method including the loss due vena contracta.
5 Nodes
The liquid level in the vessel. Pressure drop is calculated based
Pressure drop calculation is ignored
Pressure drop ismethod but
Pressure drop is calculated in accordance withmethod including the loss due vena contracta.
5 Nodes 53
Field Description
IsothermalPressure Drop
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the separator will not update duringiterative calculations for pressure loss i.e. a PT flash will be used toupdate the inlet properties. If the option is set to No, a morerigorous PH flash will be used to update the inlet properties.
The horizontal separator does three size change calculations, onebetween each stream connection and the vessel body. Normallythese will be expansion calculations for the primary and secondaryinlets and a contraction calculation for the vapor outlet but theywill automatically change if flows are reversed.
Setting this option to Yes can speed up calculations in some casesat cost of a minor loss of accuracy.
Size Change Group
Two PhaseCorrection
If this option is set to Yes, the pressure loss coefficient in twophase flow will be calculated using properties corrected for liquidslip. If set to No, the homogenous properties of the fluid will beused in calculating the pressure loss coefficient.
Method The following options are available:
Compressible - Pressure losses will be calculated assumingcompressible flow through the connector at all times.
Incompressible (Crane) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using Cranecoefficients.
Transition - Pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressibleflow method.
Incompressible (HTFS) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using HTFScorrelations
The Incompressible method calculations are faster but will beless accurate at higher pressure drops. The Transition methodcan cause instabilities in some cases if the calculated pressuredrop is close to the transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
54
Field
BodyDimension
Composition Tab
If the inlet feed flashes in the separator and as a result ofmixture is converted into liquid fully andThis can cause instability in the pressure solution of the whole network. Toavoid this, Aspen Flare System Analyzervery small vapor fraction for the vapor outlet (<0.001%).composition of the vapor phase here.
Fig 5.11
Description
If this option is set to Full Body Area, the calculation for theprimary inlet/vessel and secondary inlet/vessel size change wiuse the whole vessel area. If Partial Body Area on Flowselected, the vessel area is reduced in proportion to theappropriate flow, i.e. if the secondary inlet volumetric flow is 20%of the total volumetric flow in the tee then 20% of the body areawill be used in the size change calculation. The use of theBody Area on Flow option has the effect of increasing thepressure loss calculated by simple fixed K factors.
Composition Tab
If the inlet feed flashes in the separator and as a result of the flash, theis converted into liquid fully and the vapor outlet will have no flow.
instability in the pressure solution of the whole network. ToAspen Flare System Analyzer creates an arbitrary vapor phase with
all vapor fraction for the vapor outlet (<0.001%). Youcomposition of the vapor phase here.
5 Nodes
the calculation for theprimary inlet/vessel and secondary inlet/vessel size change will
Partial Body Area on Flow isthe vessel area is reduced in proportion to the
i.e. if the secondary inlet volumetric flow is 20%of the total volumetric flow in the tee then 20% of the body area
ill be used in the size change calculation. The use of the Partialoption has the effect of increasing the
pressure loss calculated by simple fixed K factors.
the flash, thethe vapor outlet will have no flow.
instability in the pressure solution of the whole network. Tocreates an arbitrary vapor phase with
can specify the
5 Nodes
Design Tab
Fig 5.12
Field
Min Drop Diameter
Drain Volume
Maximum Holdup time
Design Length
Settling Velocity
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
Design Tab
Description
Min Drop Diameter Enter the diameter of the minimum drop size to beremoved.
Enter the drain volume.
Maximum Holdup time Enter maximum holdup time before the horizontalseparator will be drained.
Minimum length of the horizontal separator required tosatisfy design conditions.
Settling velocity of the minimum drop size to be removed.
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
55
Enter the diameter of the minimum drop size to be
Enter maximum holdup time before the horizontal
ength of the horizontal separator required to
minimum drop size to be removed.
The result of the calculations at each of the pipe connections is displayed.
56
Fig 5.13
Orifice PlateAn Orifice Plateperpendicular to the flat upstream face of the plate placed crossways in thepipe. Orifice plates are generally used to restrict the flow downstream of ablow down valve or restrict the flow from a high pressure section of a flaresystem to a low pressure section. They may also be used to allow flowmeasurement.
Connections Tab
The name of the orifice plate and connectivity information is specified here.
Orifice PlateOrifice Plate is a thin plate, which has a clean-cut hole with straight walls
perpendicular to the flat upstream face of the plate placed crossways in thepipe. Orifice plates are generally used to restrict the flow downstream of ablow down valve or restrict the flow from a high pressure section of a flareystem to a low pressure section. They may also be used to allow flow
Connections Tab
The name of the orifice plate and connectivity information is specified here.
5 Nodes
ole with straight wallsperpendicular to the flat upstream face of the plate placed crossways in thepipe. Orifice plates are generally used to restrict the flow downstream of ablow down valve or restrict the flow from a high pressure section of a flareystem to a low pressure section. They may also be used to allow flow
The name of the orifice plate and connectivity information is specified here.
5 Nodes
Fig 5.14
The following fields are available on this tab:
Field
Name
Location
Upstream/Downstream
At
Ignore
Calculations Tab
Calculation methods are specified here.
The following fields are available on this tab:
Description
The alphanumeric description of the Orifice PlateHP OP).
You may want to specify the location of theplant.
Upstream/Downstream Either type in the name of the pipe segment or select fromthe list.
You can specify the end of the pipe segment attached tothe orifice plate.
Select the Ignore check box to ignore this orificethe calculations. Clear the check box to re-
Calculations Tab
Calculation methods are specified here.
57
Orifice Plate (e.g. -
You may want to specify the location of the node in the
Either type in the name of the pipe segment or select from
e end of the pipe segment attached to
box to ignore this orifice plate in-enable it.
58
Fig 5.15
Note: You only need to provide 1 of 3 sizing parameters. For Example, if youentered the DiameterUpstream Diameter Ratio
The following fields are available on this tab:
Field Description
Dimensions Group
Diameter
UpstreamDiameter Ratio
DownstreamDiameter Ratio
Methods Group
Fitting LossMethod
The following options
ou only need to provide 1 of 3 sizing parameters. For Example, if youDiameter, Aspen Flare System Analyzer will then
Upstream Diameter Ratio and the Downstream Diameter Ratio
The following fields are available on this tab:
Description
Dimensions Group
The diameter of the orifice hole.
The ratio of the throat diameter to the upstream pipe diameter.
The ratio of the throat diameter to the downstream pipe diameter
The following options are available:
Ignored - If this option is selected, the fitting losses for theorifice plate would not be calculated. Static pressure isbalanced.
Thin Orifice - The fitting losses for the orifice plate will becalculated using the equations for the thin orifice plate.
Contraction/Expansion - For this method, orifice plates will bemodeled as a sudden contraction from the inlet line size tothe diameter of the hole followed by a sudden expansionthe diameter of the hole to the outlet line size.
5 Nodes
ou only need to provide 1 of 3 sizing parameters. For Example, if youthen calculate the
Downstream Diameter Ratio.
ratio of the throat diameter to the upstream pipe diameter.
he ratio of the throat diameter to the downstream pipe diameter.
If this option is selected, the fitting losses for theorifice plate would not be calculated. Static pressure is
ice plate will becalculated using the equations for the thin orifice plate.
For this method, orifice plates will bemodeled as a sudden contraction from the inlet line size tothe diameter of the hole followed by a sudden expansion fromthe diameter of the hole to the outlet line size.
5 Nodes 59
Field Description
IsothermalPressureDrop
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the orifice plate will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to update theinlet properties. If the option is set to No, a more rigorous PH flashwill be used to update the inlet properties.
The orifice plate will do one contraction calculation and one expansioncalculation if the Fitting Loss Method is set toContraction/Expansion. Setting this option to Yes can speed upcalculations in some cases at cost of a minor loss of accuracy.
Size Change Group
Two PhaseCorrection
If this option is set to Yes, the pressure loss coefficient in two phaseflow will be calculated using properties corrected for liquid slip. If setto No, the homogeneous properties of the fluid will be used incalculating the pressure loss coefficient.
Method The following options are available:
Compressible - Pressure losses will be calculated assumingcompressible flow through the connector at all times.
Incompressible (Crane) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using Cranecoefficients.
Transition - Pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressible flowmethod.
Incompressible (HTFS) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using HTFScorrelations.
The Incompressible method calculations are faster but will be lessaccurate at higher pressure drops. The Transition method can causeinstabilities in some cases if the calculated pressure drop is close tothe transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
60
Summary Tab
Fig 5.16
The result of the calculations at each of the pipe connections is displayed.
TeeThe Tee is used to model the connection of three pipespipes may be different.
Connections Tab
The name of the tee and connectivity information is specified here.
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
is used to model the connection of three pipes. The diameters of thepipes may be different.
Connections Tab
The name of the tee and connectivity information is specified here.
5 Nodes
The result of the calculations at each of the pipe connections is displayed.
. The diameters of the
The name of the tee and connectivity information is specified here.
5 Nodes
Fig 5.17
You only need to provide 2 of 3 connections to be able to solve the tee. Thisallows for solution(s) to partially
The following fields are available on this tab:
Field
Name
Location
Upstream/Downstream/Branch
At
Ignore
Calculations Tab
Calculation methods are specified here.
You only need to provide 2 of 3 connections to be able to solve the tee. Thisallows for solution(s) to partially built networks.
The following fields are available on this tab:
Description
The alphanumeric description of theTee 1).
You may want to specify the location of the node inthe plant. The location can have an alphanumername. This feature is useful for large flowsheets,because you can provide a different “location” nameto different sections to make it more comprehensible.
Upstream/Downstream/Branch Either type in the name of the pipe segment or selectfrom the list.
You can specify the end of the pipe segment attachedwith the tee.
Select the Ignore check box to ignore this tee in thecalculations. Clear the check box to re
Calculations Tab
Calculation methods are specified here.
61
You only need to provide 2 of 3 connections to be able to solve the tee. This
The alphanumeric description of the Tee (e.g. - HP
You may want to specify the location of the node inthe plant. The location can have an alphanumericname. This feature is useful for large flowsheets,because you can provide a different “location” nameto different sections to make it more comprehensible.
Either type in the name of the pipe segment or select
You can specify the end of the pipe segment attached
box to ignore this tee in thebox to re-enable it.
62
Fig 5.18
The following fields are available on this tab:
Field Description
Dimensions Group
Theta Specify thetee.
Body Specify the diameter of the body of the tee.
Methods Group
e following fields are available on this tab:
Description
Dimensions Group
Specify the angle of the branch to the upstream connectiontee.
Specify the diameter of the body of the tee. Allowable choices are:
Run - The diameter will be that of the inlet pipe.
Tail - The diameter will be that of the outlet pipe.
Branch - The diameter will be that of the branch pipe.
Auto - Set the body diameter to be larger of the inlet andbranch pipe diameters.
5 Nodes
connection of the
Allowable choices are:
ill be that of the inlet pipe.
he diameter will be that of the outlet pipe.
he diameter will be that of the branch pipe.
the body diameter to be larger of the inlet and
5 Nodes 63
Field Description
Fitting LossMethod
The available options are:
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Simple - This method uses a constant, flow rationindependent K factor for the loss through the branch andrun.
Miller - This method uses a K factor which is interpolatedusing Miller Curves, which are functions of the flow and arearatios of the branch to the total flow as well as the branchangle. Loss coefficients at low values of the branch are tobody area are extrapolated from the data presented on thecharts.
Miller (Area Ratio Limited) – This method uses a K factorwhich is interpolated using Miller Curves, which arefunctions of the flow and area ratios of the branch to thetotal flow as well as the branch angle. The ratio of thebranch area to body area is constrained by the lower limitpresented on the charts.
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Gardel – This method calculates the K factor using theanalytical equations of Gardel.
Miller ChartExtrapolation
The available options are:
None – No extrapolation is used. If the data falls outside theMiller chart, a fixed value of K (K=8.0) is used.
Miller Area Ratio Squared – Uses a K factor which isextrapolated using Miller Curves, assuming that the Kfactors are functions of the flow and area ratio squared, ofthe branch to the total flow as well as the branch angle.
Gardel – Uses the Gardel method to calculate K factor if theK factor is out of bounds in miller chart.
Connector IfIncomplete
If this option is set to Yes, Aspen Flare System Analyzer will treatthe Tee as a straight connector, ignoring the effect of the branch onpressure drop.
The Tee will do three size change calculations between inlet/body,branch/body and body/outlet selecting expansion or contractioncalculations as appropriate.
Setting this option to Yes can speed up calculations in some casesat cost of a minor loss of accuracy.
IsothermalPressure Drop
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the tee will not update during iterativecalculations for pressure loss, i.e. a PT flash will be used to updatethe inlet properties. If the option is set to No, a more rigorous PHflash will be used to update the inlet properties.
Swage Method Group
Two PhaseCorrection
If this option is set to Yes, the pressure loss coefficient in two phaseflow will be calculated using properties corrected for liquid slip. If setto No, the homogenous properties of the fluid will be used incalculating the pressure loss coefficient.
64 5 Nodes
Field Description
Method The following options are available:
Compressible - Pressure losses will be calculated assumingcompressible flow through the tee at all times.
Incompressible (Crane) - Pressure losses will be calculatedassuming incompressible flow through the tee at all times.Loss coefficients are calculated using Crane coefficients.
Transition - Pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressibleflow method.
Incompressible (HTFS) - Pressure losses will be calculatedassuming incompressible flow through the tee at all times.Loss coefficients are calculated using HTFS correlations.
The Incompressible method calculations are faster but will be lessaccurate at higher pressure drops. The Transition method cancause instabilities in some cases if the calculated pressure drop isclose to the transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
BodyDimension
If this option is set to Full Body Area, the calculation for theinlet/body and branch/body size change will use the whole bodyarea. If Partial Body Area on Flow is selected, the body area isreduced in proportion to the appropriate flow, i.e. if the branchvolumetric flow is 20% of the total volumetric flow in the tee then20% of the body area will be used in the size change calculation.This option is ignored if the fittings loss method is set to Miller. Theuse of the Partial Body Area on Flow option has the effect ofincreasing the pressure loss calculated by simple fixed K factorsbringing the results closer to those calculated by the ore accurateMiller K factors.
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
5 Nodes
Fig 5.19
Vertical SeparatorVertical separators are used to allow liquid to separate from the feed streamso that it can be removed from the flare system. The liquid phase in thevertical separator feed is removed from the network. In Aspen Flare SystemAnalyzer, the Vertical Separatorstream.
Connections Tab
The name of the vertical separator and connectivity information is specifiedhere.
Vertical Separatoreparators are used to allow liquid to separate from the feed stream
so that it can be removed from the flare system. The liquid phase in theeparator feed is removed from the network. In Aspen Flare System
Vertical Separator has only one inlet and one vapor outlet
Connections Tab
The name of the vertical separator and connectivity information is specified
65
eparators are used to allow liquid to separate from the feed streamso that it can be removed from the flare system. The liquid phase in the
eparator feed is removed from the network. In Aspen Flare Systemhas only one inlet and one vapor outlet
The name of the vertical separator and connectivity information is specified
66
Fig 5.20
The location can have an alphanumeric name. This feature is useful forflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Field Description
Name The alphanumeric description of theDrum).
Location You may want to specify the location of the
Inlet/Outlet Either type in the name of the pipe segment or select from the list.
At You can specify the end of the pipe segment attached to theseparato
Ignore Select thecalculations. Clear the check
Calculations Tab
Calculation methods are specified here.
The location can have an alphanumeric name. This feature is useful forflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Description
The alphanumeric description of the Vertical SeparatorDrum).
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select from the list.
You can specify the end of the pipe segment attached to theeparator.
Select the Ignore check box to ignore this vertical separator in thecalculations. Clear the check box to re-enable it.
Calculations Tab
Calculation methods are specified here.
5 Nodes
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to different
Vertical Separator (e.g. - HP KO
in the plant.
Either type in the name of the pipe segment or select from the list.
You can specify the end of the pipe segment attached to the vertical
box to ignore this vertical separator in the
5 Nodes
Fig 5.21
The following fields are available on this tab:
Field D
Diameter The internal diameter of the vessel.
Methods Group
Fitting LossMethod
The available options are:
IsothermalPressure Drop
If this optiochange calculations in the separator will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to updatethe inlet properties. If the option is set toflash will be used to update the inlet properties.
The vertical separator will do one expansion calculation for the inletstream entering the vessel and one contraction calculation for theflow from the vessel to the outlet. These will automaticflows through the vessel are reversed.
Setting this option toat cost of a minor loss of accuracy.
Size Change Group
The following fields are available on this tab:
Description
The internal diameter of the vessel.
The available options are:
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Calculated Ignore Vena Contracta – Pressure drop iscalculated in accordance with the Swage method butignores the loss due vena contracta.
Calculated – Pressure drop is calculated in accordance withthe Swage method including the loss due vena contracta.
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the separator will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to updatethe inlet properties. If the option is set to No, a more rflash will be used to update the inlet properties.
The vertical separator will do one expansion calculation for the inletstream entering the vessel and one contraction calculation for theflow from the vessel to the outlet. These will automaticflows through the vessel are reversed.
Setting this option to Yes can speed up calculations in some casesat cost of a minor loss of accuracy.
Size Change Group
67
Pressure drop calculation is ignored
sure drop ismethod but
Pressure drop is calculated in accordance withmethod including the loss due vena contracta.
, the inlet temperatures used for the sizechange calculations in the separator will not update during iterativecalculations for pressure loss i.e. a PT flash will be used to update
a more rigorous PH
The vertical separator will do one expansion calculation for the inletstream entering the vessel and one contraction calculation for theflow from the vessel to the outlet. These will automatically change if
can speed up calculations in some cases
68 5 Nodes
Field Description
Two PhaseCorrection
If this option is set to Yes, the pressure loss coefficient in two phaseflow will be calculated using properties corrected for liquid slip. If setto No, the homogenous properties of the fluid will be used incalculating the pressure loss coefficient.
Method The following options are available:
Compressible - Pressure losses will be calculated assumingcompressible flow through the connector at all times.
Incompressible (Crane) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using Cranecoefficients.
Transition - Pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressibleflow method.
Incompressible (HTFS) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using HTFScorrelations.
The Incompressible method calculations are faster but will be lessaccurate at higher pressure drops. The Transition method cancause instabilities in some cases if the calculated pressure drop isclose to the transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
Composition Tab
If the inlet feed flashes in the separator, as a result of the flash, the mixtureis converted into liquid fully and the vapor outlet will have no flow. This cancause instability in the pressure solution of the whole network. To avoid this,Aspen Flare System Analyzer creates an arbitrary vapor phase with very smallvapor fraction for the vapor outlet (<0.001%). You can specify thecomposition of the vapor phase here.
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Fig 5.22
69
70
Design Tab
Fig 5.23
Field
Min Drop Diameter
Design Diameter
Settling Velocity
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
Design Tab
Description
Min Drop Diameter Enter the diameter of the minimum drop size to beremoved.
Minimum diameter of the vertical separator required tosatisfy design conditions.
Settling velocity of the minimum drop size to be removed.
Summary Tab
The result of the calculations at each of the pipe connections is displayed.
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Enter the diameter of the minimum drop size to be
Minimum diameter of the vertical separator required to
elocity of the minimum drop size to be removed.
The result of the calculations at each of the pipe connections is displayed.
5 Nodes
Fig 5.24
Boundary NodesThe following types of boundary nodes are available in Aspen Flare SystemAnalyzer. A bounda
Control Valve
Relief Valve
Flare Tip
The relief valve and control valve node types represent sources or inflows intothe system. Thealternative types of sourcespurge valves.
Control ValveThe Control Valvevalves, bursting disks and blow down valves. The most significant differenceto the Relief Valve
Connections Tab
The name of the control valve and connectivity information is specified here.
Boundary NodesThe following types of boundary nodes are available in Aspen Flare SystemAnalyzer. A boundary node is one that is connected to only one pipe segment.
Control Valve
Relief Valve
The relief valve and control valve node types represent sources or inflows intothe system. The Control Valve, in particular, may also be used to model
ive types of sources, such as blow down valves, rupture disks, and
Control ValveControl Valve is used to model a constant flow source, such as purge
ting disks and blow down valves. The most significant differenceRelief Valve is that the rated flow equals the nominal flow.
Connections Tab
The name of the control valve and connectivity information is specified here.
71
The following types of boundary nodes are available in Aspen Flare Systemry node is one that is connected to only one pipe segment.
The relief valve and control valve node types represent sources or inflows into, in particular, may also be used to model
rupture disks, and
such as purgeting disks and blow down valves. The most significant difference
is that the rated flow equals the nominal flow.
The name of the control valve and connectivity information is specified here.
72
Fig 5.25
The location can hflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Field Description
Name The al
Location You may want to specify the location of the
Outlet Either type in the name of the pipe segment or select from the list.
At You can specify where the pipe segment isvalve.
Ignore Select thecalculations. Clear the check
Conditions Tab
Fluid conditions are specified here.
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Description
The alphanumeric description of the Control Valve (e.g.
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select from the list.
You can specify where the pipe segment is to be attached to thealve.
Select the Ignore check box to ignore this control valve in thecalculations. Clear the check box to re-enable it.
Conditions Tab
Fluid conditions are specified here.
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ave an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to different
(e.g. - FCV 1).
in the plant.
Either type in the name of the pipe segment or select from the list.
to be attached to the control
box to ignore this control valve in the
5 Nodes
Fig 5.26
It is recommended that a valueto an isenthalpic flash from the upstream conditions down to theBack Pressure. This will give the highest probable entry temperature intothe system which will in turn give the highest velocities.
The following fields are available on this tab:
Field Description
Conditions Group
Inlet Pressure
Inlet Temp.Spec.
It is recommended that a value for Outlet Temperature which correspondsto an isenthalpic flash from the upstream conditions down to the
. This will give the highest probable entry temperature intothe system which will in turn give the highest velocities.
lowing fields are available on this tab:
Description
Conditions Group
The pressure of the source on the upstream side of the valve.
The temperature specification of the source on the upsof the control valve. You can select the fluid condition from the liston the left side. The available options are:
Actual - The given inlet temperature is the actual fluidtemperature.
Superheat - If this option is selected, enter the amount ofsuperheat.
Subcool - If this option is selected, enter the amount ofsubcooling.
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which correspondsto an isenthalpic flash from the upstream conditions down to the Allowable
. This will give the highest probable entry temperature into
The pressure of the source on the upstream side of the valve.
The temperature specification of the source on the upstream sideYou can select the fluid condition from the list
The given inlet temperature is the actual fluid
If this option is selected, enter the amount of
s option is selected, enter the amount of
74 5 Nodes
Field Description
Allowable BackPressure
The Allowed Back Pressure is the pressure that is allowed toexist at the outlet of a pressure relief device as a result of thepressure in the discharge system. It is the sum of thesuperimposed and built-up back pressure. Clicking Set calculatesthe Allowable Back Pressure as a function of the InletPressure. Selecting the Auto check box will automaticallycalculate the Allowable Back Pressure whenever the InletPressure changes.
OutletTemperature
This is the temperature of the source at the flange on thedownstream side of the valve.
If the enthalpy method chosen is the Ideal Gas model, thistemperature is used to determine the enthalpy of the source at theentrance to the pipe network; otherwise, this enthalpy is calculatedfrom the upstream pressure and temperature. If Set was clicked,and the enthalpy model is Peng Robinson, Soave RedlichKwong or Lee Kesler, the outlet temperature will be calculatedfrom the upstream temperature and pressure after isenthalpicexpansion to the defined Allowable Back Pressure.
Mass Flow This is the mass flow of the source. This is generally the flow rategenerated by the upset condition.
Dimensions Group
FlangeDiameter
This is the diameter of the flange at the valve discharge. The flangediameter may be left unknown in which case it will be assumed to bethe same as the outlet pipe.
Composition Tab
The fluid composition is specified here.
5 Nodes
Fig 5.27
The following fields are available on
Field Description
Basis TMole Fraction
Mol. Wt. Thethe composition basis selected is
If the composition basis selected isFractionchange the component fractions.
Fluid Type Ifto calculate a binaryweight. If the two components of the specified fluid type are notfound
ComponentFractions
The fluid composition in either mole or mass fractions. You can onlyenter data here iffractions. You can normalize the composition either manually editingthe component fractions or by clicking
If the compositioncomponent fractions are estimaweight.
The following fields are available on this tab:
Description
The composition basis, which may be either MolecularMole Fraction or Mass Fraction.
The molecular weight of the fluid. You can only enter data here ifthe composition basis selected is molecular weight.
If the composition basis selected is Mole FractionFraction, the molecular weight is updated when you enter orchange the component fractions.
If molecular weight is selected , you need to select theto calculate a binary composition in order to match the molecularweight. If the two components of the specified fluid type are notfound, the other components are used.
The fluid composition in either mole or mass fractions. You can onlyenter data here if the composition basis selected is mole or massfractions. You can normalize the composition either manually editingthe component fractions or by clicking Normalise.
If the composition Basis selected is molecular weight, thecomponent fractions are estimated when you change the molecularweight.
75
ecular Weight,
molecular weight of the fluid. You can only enter data here if.
or Mass, the molecular weight is updated when you enter or
you need to select the Fluid Typecomposition in order to match the molecular
weight. If the two components of the specified fluid type are not
The fluid composition in either mole or mass fractions. You can onlythe composition basis selected is mole or mass
fractions. You can normalize the composition either manually editing
selected is molecular weight, theted when you change the molecular
76
Field Description
CloneCompositionFrom
This button allows the copying of compositional data from anothercontrol
Normalise Normalises the composition such that the sum of the componentfractions is 1.
Methods Tab
Calculation methods are specified here.
Fig 5.28
The following fields are available on this tab:
Fields Description
Description
This button allows the copying of compositional data from anothercontrol valve in the same scenario.
Normalises the composition such that the sum of the componentfractions is 1.
Methods Tab
Calculation methods are specified here.
The following fields are available on this tab:
Description
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This button allows the copying of compositional data from another
Normalises the composition such that the sum of the component
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Fields Description
VLE Method The options for the Vapor-Liquid Equilibrium calculations are asfollows (see Chapter 9 Theoretical Basis):
Compressible Gas – Real Gas relationship. This is onlyavailable when the Enthalpy Method on the CalculationOptions Editor is Ideal Gas.
Peng Robinson – Peng Robinson Equation of State. This isonly available when the Enthalpy Method on theCalculation Options Editor is NOT Ideal Gas.
Soave Redlich Kwong – Soave Redlich Kwong Equation ofState. This is only available when the Enthalpy Method onthe Calculation Options Editor is NOT Ideal Gas.
Vapour Pressure – Vapour Pressure method as described inAPI Technical Data Book– Volume 113. This is only availablewhen the Enthalpy Method on the Calculation OptionsEditor is NOT Ideal Gas.
Model Default - If this is selected, the Default method forthe VLE method (as defined on the Calculation OptionsEditor) will be used.
Swage Group
Fitting LossMethod
The available options are;
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Calculated – Pressure drop is calculated in accordance withthe Swage method.
IsothermalPressure Drop
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the control valve will not update duringiterative calculations for pressure loss i.e. a PT flash will be used toupdate the inlet properties. If the option is set to No, a morerigorous PH flash will be used to update the inlet properties.
The control valve will do one size change calculation from thedefined flange diameter to the outlet pipe diameter. This willnormally be an expansion.
Setting this option to Yes can speed up calculations in some casesat cost of a minor loss of accuracy.
Two PhaseCorrection
If this option is set to Yes, the pressure loss coefficient in two phaseflow will be calculated using properties corrected for liquid slip. If setto No, the homogeneous properties of the fluid will be used incalculating the pressure loss coefficient.
78 5 Nodes
Fields Description
Method The following options are available:
Compressible - Pressure losses will be calculated assumingcompressible flow through the connector at all times.
Incompressible (Crane) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using Cranecoefficients.
Transition - Pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressibleflow method.
Incompressible (HTFS) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using HTFScorrelations.
The Incompressible method calculations are faster but will be lessaccurate at higher pressure drops. The Transition method cancause instabilities in some cases if the calculated pressure drop isclose to the transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
Estimated Properties at Header Conditions Group
VapourFraction
The initial estimates for the flow profile in looped systems aregenerated based on the assumption of vapor phase flow without anyliquid knockout in the system. It is not uncommon for sources topass through a knockout drum before connection to the mainheader. Specification of an estimate of vapor fraction of the fluid atthe knockout drum can considerably enhance the automaticallygenerated flow profile. If not specified, for the initial estimates, thefluid is assumed to be vapor only at the header condition.
Vapour Mol.Wt.
Specify the estimated vapor molecular weight for the vapor fractiongiven above. If provided, this value is used to assist the automaticgeneration of the flow profile for looped systems. If not specified, forthe initial estimates, the vapour molecular weight is assumed to bethe same as the overall fluid molecular weight at the headercondition.
Inlet Piping Tab
Details of the piping between the protected equipment and the inlet to thecontrol valve are specified here. This data is used to calculate the pressuredrop in the inlet piping. The diameter of the inlet piping is also used tocalculate the inlet velocity of the source fluid when the Include KineticEnergy option is selected in the Calculation Options Editor.
5 Nodes
Fig 5.29
The available fields are:
Fields Description
Routing Group
Length The length of the inlet piping.
ElevationChange
The change in elevation of the inlet piping. Ththan the length of the piping.
Properties Group
Material The material of the inlet pipeSteel
Roughness The surface roughness of the inlet pipe. Whenever a material isselected, the absolute roughnthe material as defined on the
Diameter Group
NominalDiameter
The nominal pipe diameter used to describe the inlet pipe size. Forpipes with a nominal diameter of 14 inches or more, this wisame as the outside diameter of the pipe.
Schedule If a pipe schedule is selected, you will be able to select a nominal pipediameter from the pipe databases. It will not be necessary to specifythe internal diameter.
The available fields are:
Description
The length of the inlet piping.
The change in elevation of the inlet piping. This cannot be greaterthan the length of the piping.
Properties Group
The material of the inlet pipe, either Carbon Steel orSteel.
The surface roughness of the inlet pipe. Whenever a material isselected, the absolute roughness is initialized to the default value forthe material as defined on the Preferences Editor.
Diameter Group
The nominal pipe diameter used to describe the inlet pipe size. Forpipes with a nominal diameter of 14 inches or more, this wisame as the outside diameter of the pipe.
If a pipe schedule is selected, you will be able to select a nominal pipediameter from the pipe databases. It will not be necessary to specifythe internal diameter.
79
is cannot be greater
or Stainless
The surface roughness of the inlet pipe. Whenever a material isess is initialized to the default value for
The nominal pipe diameter used to describe the inlet pipe size. Forpipes with a nominal diameter of 14 inches or more, this will be the
If a pipe schedule is selected, you will be able to select a nominal pipediameter from the pipe databases. It will not be necessary to specify
80
Fields Description
InternalDiameter
The pipe
Use PipeClass
Selectdefined by the
Fittings Groups
LossCoefficient
Enter the A and B parameters for the following fittequation in which Fflow:
K = A +
Summary Tab
The result of the calculations is displayed.
Fig 5.30
Description
The pipe diameter used for the pressure drop calculations.
Select Yes to restrict the sizes of the inlet piping selected to thosedefined by the Pipe Class tool.
Enter the A and B parameters for the following fittings K factorequation in which Ft is the friction factor for fully developed turbulentflow:
K = A + BFt
Summary Tab
The result of the calculations is displayed.
5 Nodes
diameter used for the pressure drop calculations.
to restrict the sizes of the inlet piping selected to those
ings K factoris the friction factor for fully developed turbulent
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Relief ValveThe Relief Valve source can be used to model types of spring loaded reliefvalves. Relief valves are used frequently in many industries in order toprevent dangerous situations occurring from pressure build
Connections Tab
The name of the relief valve and connectivity information is specified here.
Fig 5.31
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it
ief Valvesource can be used to model types of spring loaded relief
valves. Relief valves are used frequently in many industries in order toprevent dangerous situations occurring from pressure build-ups in a system.
Connections Tab
ame of the relief valve and connectivity information is specified here.
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
81
source can be used to model types of spring loaded reliefvalves. Relief valves are used frequently in many industries in order to
ups in a system.
ame of the relief valve and connectivity information is specified here.
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to different
82 5 Nodes
The following fields are available on this tab:
Field Description
Name The alphanumeric description of the Relief Valve (e.g. - FCV 1).
Location You may want to specify the location of the node in the plant.
Outlet Either type in the name of the pipe segment or select from the list.
At You can specify where the pipe segment is to be attached to the reliefvalve.
Ignore Select the Ignore check box to ignore this relief valve in thecalculations. Clear the check box to re-enable it.
Conditions Tab
Fluid conditions are specified here.
5 Nodes
Fig 5.32
It is recommended that a value forto an isenthalpic flash from the upstream conditions down to theBack Pressure. This will give the highestthe system which will in turn give the highest velocities.
The following fields are available on this tab:
Field
Conditions Group
MAWP
It is recommended that a value for Outlet Temperature which correspondsto an isenthalpic flash from the upstream conditions down to the
. This will give the highest probable entry temperature intothe system which will in turn give the highest velocities.
The following fields are available on this tab:
Description
Conditions Group
The Maximum Allowable Working Pressure (MAWPmaximum gauge pressure permissible in a vessel at its operatingtemperature. It is normally equal to the relief valve set pressureunless you have a low pressure vessel.
83
which correspondsto an isenthalpic flash from the upstream conditions down to the Allowable
probable entry temperature into
MAWP) is thee permissible in a vessel at its operating
temperature. It is normally equal to the relief valve set pressure
84 5 Nodes
Field Description
Contingency In general there are two types of process upset conditions:
Operating - The relieving pressure is 110% of MAWPunless you have a multiple valve assembly in which case itis 116% of MAWP. Some of the operating upset examplesare cooling failure, power failure and instrument air failure.
Fire - The relieving pressure is 121% of MAWP.
RelievingPressure
The Relieving Pressure is equal to the valve set pressure plus theoverpressure. You can either enter the value or have it calculatedusing the MAWP and the Contingency by clicking Set. If youentered a value less than the MAWP, a warning message will begenerated.
Selection of the Auto check box will automatically calculated therelieving pressure from the MAWP and Contingency wheneverthese values change.
Inlet Temp.Spec.
The temperature specification of the source on the upstream side ofthe relief valve. You can select the fluid condition from the dropdown box on the right hand side of this field. The available optionsare:
Actual - It uses the given inlet temperature as the actualfluid temperature.
Superheat - If this option is selected, enter the amount ofsuperheat.
Subcool - If this option is selected, enter the amount ofsubcooling.
Allowable BackPressure
The Allowable Back Pressure is the pressure that is allowed toexist at the outlet of a pressure relief device as a result of thepressure in the discharge system. It is the sum of thesuperimposed and built-up back pressure. Clicking Set calculatesthe Allowable Back Pressure as a function of the valve type andMAWP.
If the Auto check box is selected then the allowed back pressure isautomatically updated whenever the valve type or MAWP ischanged.
OutletTemperature
This is the temperature of the source on the downstream side ofthe valve.
If the enthalpy method chosen is the Ideal Gas model, then thistemperature is used to determine the enthalpy of the source at theentrance to the pipe network, otherwise this enthalpy is calculatedby isenthalpic flash from the upstream pressure and temperature.
If Set is pressed and the enthalpy model is Peng Robinson,Soave Redlich Kwong or Lee Kesler, the outlet temperature willbe calculated from the upstream temperature and pressure afterexpansion to the defined Allowable Back Pressure.
Mass Flow The nominal mass flow of the source. This is generally the flowrategenerated by the upset condition.
Rated Flow It is the rated mass flow of the source. This is generally theflowrate that the relief valve is capable of passing.
Clicking Set calculates the rated flow from the MAWP, valve type,orifice area, valve count, upstream pressure, upstream temperatureand sizing method. If the Auto check box is selected, the ratedflow will be automatically updated after any change in these values.
Rated Flow Parameters
5 Nodes 85
Field Description
K(Cp/Cp-R) K is the Ideal Gas ratio of specific heats.
Compressibility Compressibility Factor for the deviation of the actual gas from aperfect gas evaluated at inlet conditions. (Z= PV/MRT)
Valve Design Group
FlangeDiameter
The diameter of the valve discharge flange. The flange diametermay be left unknown in which case it will be assumed to be thesame as the outlet pipe.
Number ofValves
Specify the number of valves for the source.
Orifice AreaPer Valve
The orifice area per valve may be set by selecting the orifice sizecode from the list. The corresponding orifice area will then bedisplayed. If the size code is set to the blank entry, the orifice areaper valve may be entered manually.
Valve Type The choices are:
Balanced - A spring loaded pressure relief valve thatincorporates a means for minimizing the effect of backpressure on the performance characteristics.
Conventional - A spring loaded pressure relief valve whoseperformance characteristics are directly affected by changesin the back pressure on the valve.
Pilot - A pilot-operated pressure relief valve in which thepilot is a self-actuated device. The major relieving device iscombined with and is controlled by the pilot.
Mech. BP Limit The maximum mechanical back pressure that can be applied to thevalve.
Composition Tab
The fluid composition is specified here.
86
Fig 5.33
The following fields are available on this tab:
Field Description
Basis The composition basis, which may be eitherFraction
Mol. Wt. The molecular weight of the fluid. You can only enter data here if thecompositi
If the composition basis selected isthe molecular weight is updated when you enter or change thecomponent fractions.
Fluid Type If Molecular Weight is selected in the composition basselect thematch the molecular weight. If the two components of the specified fluidtype are not found
e following fields are available on this tab:
Description
The composition basis, which may be either MolecularFraction or Mass Fraction.
he molecular weight of the fluid. You can only enter data here if thecomposition basis selected is Molecular Weight.
If the composition basis selected is Mole Fraction orthe molecular weight is updated when you enter or change thecomponent fractions.
If Molecular Weight is selected in the composition basselect the Fluid Type to calculate a binary composition in order tomatch the molecular weight. If the two components of the specified fluidtype are not found, the other components are used.
5 Nodes
ecular Weight, Mole
he molecular weight of the fluid. You can only enter data here if the
or Mass Fraction,the molecular weight is updated when you enter or change the
If Molecular Weight is selected in the composition basis list, you need toto calculate a binary composition in order to
match the molecular weight. If the two components of the specified fluid
5 Nodes 87
Field Description
ComponentFractions
The fluid composition in either mole or mass fractions. You can onlyenter data here if the composition basis selected is mole or massFraction. You can normalize the composition by either manually editingthe component fractions or by clicking Normalise.
If the composition basis selected is Molecular Weight, the componentfractions are estimated when you change the molecular weight.
CloneCompositionFrom
This button allows the copying of compositional data from another reliefvalve in the same scenario.
Normalise Normalises the composition such that the sum of the componentfractions is 1.
Methods Tab
Calculation methods are specified here.
88
Fig 5.34
The following fields are available on this tab:
Field
The following fields are available on this tab:
Description
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5 Nodes 89
Field Description
VLE Method The options for the Vapor-Liquid Equilibrium calculations are asfollows (see Chapter 9 Theoretical Basis):
Compressible Gas – Real Gas relationship. This is onlyavailable when the Enthalpy Method on the CalculationOptions Editor is Ideal Gas.
Peng Robinson – Peng Robinson Equation of State. This isonly available when the Enthalpy Method on theCalculation Options Editor is NOT Ideal Gas.
Soave Redlich Kwong – Soave Redlich Kwong Equation ofState. This is only available when the Enthalpy Methodon the Calculation Options Editor is NOT Ideal Gas.
Vapour Pressure – Vapour Pressure method as described inAPI Technical Data Book– Volume 113. This is onlyavailable when the Enthalpy Method on the CalculationOptions Editor is NOT Ideal Gas.
Model Default - If this is selected, the Default method forthe VLE method (as defined on the Calculation OptionsEditor) will be used.
Swage Group
Fitting LossMethod
The available options are;
Equal Static Pressure – Pressure drop calculation is ignoredand static pressure is balanced.
Calculated – Pressure drop is calculated in accordance withthe Swage method.
IsothermalPressure Drop
If this option is set to Yes, the inlet temperatures used for the sizechange calculations in the relief valve will not update duringiterative calculations for pressure loss i.e. a PT flash will be used toupdate the inlet properties. If the option is set to No, a morerigorous PH flash will be used to update the inlet properties.
The relief valve will do one size change calculation from thedefined flange diameter to the outlet pipe diameter. This willnormally be an expansion. Setting this option to Yes can speed upcalculations in some cases at cost of a minor loss of accuracy.
Two PhaseCorrection
If this option is set to Yes, the pressure loss coefficient in twophase flow will be calculated using properties corrected for liquidslip. If set to No, the homogeneous properties of the fluid will beused in calculating the pressure loss coefficient.
90 5 Nodes
Field Description
Method The following options are available:
Compressible - Pressure losses will be calculated assumingcompressible flow through the connector at all times.
Incompressible (Crane) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using Cranecoefficients.
Transition - Pressure losses will be calculated initially usingthe assumption of incompressible flow. If the pressure lossexpressed as a percentage of the inlet pressure is greaterthan the defined compressible transition value then thepressure drop will be recalculated using the compressibleflow method.
Incompressible (HTFS) - Pressure losses will be calculatedassuming incompressible flow through the connector at alltimes. Loss coefficients are calculated using HTFScorrelations.
The Incompressible method calculations are faster but will beless accurate at higher pressure drops. The Transition methodcan cause instabilities in some cases if the calculated pressuredrop is close to the transition value.
Balance Total Pressure – Frictional pressure drop is ignoredand total pressure is balanced between upstream &downstream.
CompressibleTransition
This entry defines the pressure drop as a percentage of the inletpressure at which compressible flow pressure drop calculationsshould be used. It applies only when the Transition method isselected.
Sizing Method Group
Sizing Method The four sizing method options available are:
API (1976) – American Petroleum Institute method in the1976 edition of RP 520 pt 1. No account is made of liquidflashing as it passes through the relief valve, thus thismethod is not recommended for either two phase orflashing fluids.
API (1993) – American Petroleum Institute method in the1993 edition of RP 520 pt 1. Liquid flashing is handled by asimplified approach in which the fluid is flashed to theoutlet pressure. The relative quantities of each phase atthe outlet condition are then used at the inlet of the valveto determine the two phase capacity
API(2000) – American Petroleum Institute method in the2000 edition of RP 520 pt 1. This method is often referredto as the Diers or Leung method. This is therecommended method for all two phase fluids.
HEM – Homogeneous Equilibrium method.
Back Pressure Back pressure to be used for rating the relief valve. If this value isnot specified, the Allowable Back Pressure is used.
MultiPhase Cd Discharge coefficient to be used of relief valve in multiphaseservice.
Liquid Cd Discharge coefficient to be used for relief valves in liquid service.
5 Nodes 91
Field Description
Kb User defined back pressure correction factor. If this field is leftblank, the back pressure correction factor is calculated. This valueshould only be specified in exceptional cases.
Energy Balance Group
Isentropic Flash Select Yes to use an isentropic flash between the inlet and outletotherwise an isenthalpic flash will be done.
IsentropicEfficiency
Fractional isentropic efficiency for the isentropic flash.
Estimated Properties at Header Conditions Group
Vapour Fraction The initial estimates for the flow profile in looped systems aregenerated based on the assumption of vapor phase flow withoutany liquid knockout in the system. It is not uncommon for sourcesto pass through a knockout drum before connection to the mainheader. Specification of an estimate of vapor fraction of the fluid atthe knockout drum can considerably enhance the automaticallygenerated flow profile. If provided, this value is used to assist theautomatic generation of the flow profile for looped systems. If notspecified, for the initial estimates, the fluid is assumed to bevapour only at the header condition.
Vapour Mol.Wt.
Specify the estimated vapor molecular weight for the vaporfraction given above. If provided, this value is used to assist theautomatic generation of the flow profile for looped systems. If notspecified, for the initial estimates, the vapour molecular weight isassumed to be the same as the overall fluid molecular weight atthe header condition.
Inlet Piping Tab
Details of the piping between the protected equipment and the inlet to therelief valve are specified here. This data is used to calculate the pressure dropin the inlet piping to ensure that it does not exceed the recommended limit of3% of the inlet pressure. The diameter of the inlet piping is also used tocalculate the inlet velocity of the source fluid when the Include KineticEnergy option is selected in the Calculation Options Editor.
92
Fig 5.35
The available fields are:
Field Description
Routing Group
Length The length of the
ElevationChange
The change in elevation of the inlet piping. Tthan the
Properties Group
Material The material of the inlet pipeSteel
Roughness The surfaceselected, the absolute roughness is initialized to the default value forthe material as defined on the
Diameter Group
The available fields are:
Description
The length of the inlet piping.
The change in elevation of the inlet piping. This cannot be greaterthan the Length of the piping.
Properties Group
The material of the inlet pipe, either Carbon Steel orSteel.
The surface roughness of the inlet pipe. Whenever a material isselected, the absolute roughness is initialized to the default value forthe material as defined on the Preferences Editor.
Diameter Group
5 Nodes
his cannot be greater
or Stainless
roughness of the inlet pipe. Whenever a material isselected, the absolute roughness is initialized to the default value for
5 Nodes 93
Field Description
NominalDiameter
The nominal pipe diameter used to describe the inlet pipe size. Forpipes with a nominal diameter of 14 inches or more, this will be thesame as the outside diameter of the pipe.
Schedule If a pipe schedule is selected, you will be able to select a nominal pipediameter from the pipe databases. It will not be necessary to specifythe internal diameter.
InternalDiameter
The pipe diameter used for the pressure drop calculations.
Use PipeClass
Select Yes to restrict the sizes of the inlet piping selected to thosedefined by the Pipe Class tool.
Fittings Groups
LossCoefficient
Enter the A and B parameters for the following fittings K factorequation in which Ft is the friction factor for fully developed turbulentflow:
K = A + BFt
Summary Tab
The result of the calculations is displayed.
94
Fig 5.36
Source ToolsThe initial sizing of a flare system is time consuming both in terms of timetaken to build the model and the computation time. Using anmethod can speed up the calculation during the initialSpeed is an important issue during sizing calculations especially for a complexmultiple scenario case. Typically, the back pressure should be used forcalculations. Rigorous rating calculation for all scenarios can be done by thePeng Robinsonpressure dependency and provides the
Source ToolsThe initial sizing of a flare system is time consuming both in terms of timetaken to build the model and the computation time. Using an Ideal Gasmethod can speed up the calculation during the initial sizing estimation.Speed is an important issue during sizing calculations especially for a complexmultiple scenario case. Typically, the back pressure should be used forcalculations. Rigorous rating calculation for all scenarios can be done by the
enthalpy method or any other enthalpy methods withpressure dependency and provides the downstream temperature.
5 Nodes
The initial sizing of a flare system is time consuming both in terms of timeIdeal Gas
sizing estimation.Speed is an important issue during sizing calculations especially for a complexmultiple scenario case. Typically, the back pressure should be used forcalculations. Rigorous rating calculation for all scenarios can be done by the
enthalpy method or any other enthalpy methods withtemperature.
5 Nodes 95
Updating Downstream Temperatures
The downstream temperatures are only used to define the system entrytemperature when ideal gas enthalpies are used. After several cycles of ratingand sizing calculations, the original values for each source may no longer bevalid. These values may be updated to reflect the results of the lastcalculation using an equation of state enthalpy method as follows:
Click Source Tools in Tools on the Home tab; select Refresh SourceTemperatures from the list.
Adding Single Source Scenarios
The thorough evaluation of a flare network will require the evaluation of manyscenarios. In most systems, there will be the possibility of each relief valvelifting on its own. In the case of a petrochemical complex, this could haveseveral hundred relief valves and the task of setting up the scenarios for eachrelief valve would be time consuming and error prone.
Once all the major scenarios have been defined, select Add Single SourceScenarios from Source Tools. Click Yes to allow Aspen Flare SystemAnalyzer to analyze the existing scenarios to determine the greatest flow ratefor each relief valve and create a scenario using this data.
Flare TipThe Flare Tip is used to model outflows from the system. It can model eitherignited combustible gas flare tips or open vents. Nonphysical equipment suchas a connection to a fixed pressure exit at a plant boundary can also bemodeled.
Connections Tab
The name of the flare tip and connectivity information is specified here.
96
Fig 5.37
The location can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Field
Name
Location
Upstream node
At
Ignore
Calculations Tab
Calculation methods are specified here.
n can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to differentsections to make it more comprehensible.
The following fields are available on this tab:
Description
The alphanumeric description of the Flare Tip (e.g.Tip).
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select from list.
You can specify the end of the pipe segment attached to the flaretip.
Select the Ignore check box to ignore this flare tip in thecalculations. Clear the check box to re-enable it.
Calculations Tab
Calculation methods are specified here.
5 Nodes
n can have an alphanumeric name. This feature is useful for largeflowsheets, because you can provide a different “location” name to different
(e.g. - HP Flare
You may want to specify the location of the node in the plant.
Either type in the name of the pipe segment or select from list.
e pipe segment attached to the flare
box to ignore this flare tip in the
5 Nodes
Fig 5.38
The following fields are a
Field
Diameter
Methods Group
Use Curves
Fitting LossCoefficient
Fittings LossCoefficient Basis
IsothermalPressure Drop
The following fields are available on this tab:
Description
You can specify a diameter for the tip. If this value is notspecified then the diameter of the connected pipe is used.
Select this check box if you are supplying pressure drop ccalculate the pressure drop of the flare tip. Data for these curvesis entered on the Curves tab.
The fitting loss coefficient will be used to calculate the pressuredrop through the flare tip.
Select whether the supplied Fittings Loss Coefficientcalculate the total pressure loss including velocity pressure lossor static pressure loss only.
If this option is set to Yes, the inlet temperatures used for thesize change calculations in the flare tip will not update duringiterative calculations for pressure loss i.e. a PT flash will be usedto update the inlet properties. If the option is set torigorous PH flash will be used to update the inlet prope
The flare tip will do a one size calculation for the change indiameter between inlet pipe and the flare tip.
Setting this option to Yes can speed up calculations in somecases at cost of a minor loss of accuracy.
97
You can specify a diameter for the tip. If this value is notspecified then the diameter of the connected pipe is used.
box if you are supplying pressure drop curves tocalculate the pressure drop of the flare tip. Data for these curves
The fitting loss coefficient will be used to calculate the pressure
Fittings Loss Coefficient willlocity pressure loss
, the inlet temperatures used for theze change calculations in the flare tip will not update during
iterative calculations for pressure loss i.e. a PT flash will be usedto update the inlet properties. If the option is set to No, a morerigorous PH flash will be used to update the inlet properties.
The flare tip will do a one size calculation for the change in
can speed up calculations in some
98
Curves Tab
User specified pressurused if the Use Curves
Fig 5.39
The following fields are available on this tab:
Field
Ref. Temp.
PressureCorrection
Mol. Wt.Extrapolation
FlowExtrapolation
Curves Tab
User specified pressure drop curves are specified here. These will only beUse Curves field on the Calculation tab is unchecked.
The following fields are available on this tab:
Description
Enter the reference temperature to which the prcurves correspond. All curves must be for the same referencetemperature.
If checked, the static pressure correction takes into accountdensity differences due to both the calculated inlet pressure andcalculated inlet pressure. The temperature correction isautomatically applied, but this box must be checked in order forpressure effects to be modeled. This box should normally bechecked.
If this is selected, extrapolation beyond the range of suppliemolecular weight curves is performed if necessary; otherwise,the bounding molecular weight curve is used.
If this is selected, extrapolation beyond the range of suppliedmass flow rates is performed if necessary; otherwise, thebounding mass flow is used.
5 Nodes
e drop curves are specified here. These will only beab is unchecked.
Enter the reference temperature to which the pressure dropcurves correspond. All curves must be for the same reference
the static pressure correction takes into accountdensity differences due to both the calculated inlet pressure and
sure. The temperature correction isbut this box must be checked in order for
pressure effects to be modeled. This box should normally be
If this is selected, extrapolation beyond the range of suppliedmolecular weight curves is performed if necessary; otherwise,
If this is selected, extrapolation beyond the range of suppliedmass flow rates is performed if necessary; otherwise, the
5 Nodes
Field
Mol. Wt.
Mass Flow/Pres.Drop
Summary Tab
The result of the calculation is displayed.
Fig 5.40
Description
Enter the molecular weight at which the pressure drop curveapplies. Add Mol. Wt. can be used to add additional curves. Thelist can then be used to select which pressure drop curve isdisplayed. Delete Mol. Wt. will delete the selected pressure dropcurve.
These pairs of data define points in the pressure drop curve.Points may be added and removed from the curve by usingPoint and Delete Point. Pressure drops for flows between thosein the table are calculated using linear interpolation.
Summary Tab
The result of the calculation is displayed.
99
Enter the molecular weight at which the pressure drop curvecan be used to add additional curves. The
list can then be used to select which pressure drop curve isthe selected pressure drop
These pairs of data define points in the pressure drop curve.Points may be added and removed from the curve by using Add
. Pressure drops for flows between thosere calculated using linear interpolation.
100 5 Nodes
6 Calculations
6 Calculations
This section provides information on the following topics:
Starting the Calculations
Efficient Modeling Techniques
Starting the CaThe following words before the object on the status bar show the type ofcalculation being performed
B = Mass and Energy Calculations
P = Pressure Drop Calculations
To start the calculations, selectthe Ribbon.
The status of the rating calculations is shown on the Status Barthe left corner of the Status Bar shows the status of the current case. Thesecond display fieliteration number, then the maximum pressure error for that iteration andfinally the name of the pipe segment responsible for the error. The thirddisplay field shows firstly the number of iteratiand then the error in the objective function being solved by the loop solver.The right corner of the Status Bar shows thethe percentage zoom setting to quickly zoom in or zoom out when viewing tProcess Flowsheet.
Fig 6.1
To abort calculations
Note: Due to speed considerations, it is recommended that sizing calculationsbe performed subject to the constraints:Enthalpy Method, or
6 Calculations
This section provides information on the following topics:
Starting the Calculations
Efficient Modeling Techniques
Starting the CalculationsThe following words before the object on the status bar show the type ofcalculation being performed:
B = Mass and Energy Calculations
P = Pressure Drop Calculations
To start the calculations, select Run from the Run group, on the
The status of the rating calculations is shown on the Status Barthe left corner of the Status Bar shows the status of the current case. Thesecond display field on the Status Bar shows firstly the inner properties loopiteration number, then the maximum pressure error for that iteration andfinally the name of the pipe segment responsible for the error. The thirddisplay field shows firstly the number of iterations taken by the loop solver,and then the error in the objective function being solved by the loop solver.The right corner of the Status Bar shows the Zoom Slider. You can slide tothe percentage zoom setting to quickly zoom in or zoom out when viewing tProcess Flowsheet.
To abort calculations, click Stop, which activates during calculations.
Due to speed considerations, it is recommended that sizing calculationsbe performed subject to the constraints: Compressible Gas VLE
, or no Heat Transfer Calculations.
101
The following words before the object on the status bar show the type of
the Home tab of
The status of the rating calculations is shown on the Status Bar. The icon onthe left corner of the Status Bar shows the status of the current case. The
d on the Status Bar shows firstly the inner properties loopiteration number, then the maximum pressure error for that iteration andfinally the name of the pipe segment responsible for the error. The third
ons taken by the loop solver,and then the error in the objective function being solved by the loop solver.
. You can slide tothe percentage zoom setting to quickly zoom in or zoom out when viewing the
during calculations.
Due to speed considerations, it is recommended that sizing calculationsVLE, Ideal Gas
102 6 Calculations
Efficient Modeling TechniquesEfficient modeling of a flare network requires some forethought in order tomeet the primary objectives which are in general:
1 Definition of the design constraints for the flare system. These are usuallydefined by company standards or by local health and safety regulations. Ifunavailable, standard texts such as API-RP-521 can be used to selectpreliminary acceptable values.
2 Efficient acquisition of the data for the piping configuration and layout.
3 Definition of the scenarios or contingencies which should be evaluated.Grass roots design will require analysis of a far wider range of scenarios tothose required by the simple expansion of a flare system to incorporate anew relief valve.
4 Rapid construction of the computer model of the flare system.
5 Fast and efficient calculation of the computer model of the flare system.
Objectives 1 to 3 can only be achieved by the use of engineering skill andjudgment. Once complete, the efficient use of Aspen Flare System Analyzercan lead to a satisfactory project conclusion.
Data EntryAspen Flare System Analyzer has a wide range of methods for entering thedata for each object within the model. In general, you should use the methodthat you are most comfortable with, but experience has shown that use of theProcess Flowsheet environment for definition of the piping configuration andlayout can save many man days of labor with large flare networks.
Although there is no set order in which the model must be built, therecommended sequence of data entry for building the model is:
1 Define the project description, user name, etc. by selecting Descriptionfrom the Application Menu which is displayed after clicking the aspenONEButton on the upper left corner of the application window.
2 Set preferences for the default piping materials, type of Tee, compositionbasis, etc. from the Preferences Editor, accessed via the ApplicationMenu. These may be overwritten on an object by object basis at anystage. Ensure that the Edit Objects On Add check box is selected if youwant to edit the object data as each new flowsheet object is created.
3 Define a pipe class if appropriate. This will ensure that you only use pipesizes as allowed by your project. Open the Pipe Class Editor in the Toolsgroup on the Home tab of the Ribbon.
4 With the Calculation Options Editor, define default calculation methodsfor VLE, Pressure Drop, etc. To open this view, click Options in the Rungroup on the Home tab.
5 Define all the source nodes (relief valves and control valves) for the firstscenario. The first scenario should be the one that has the greatest levelof common data amongst the complete set of scenarios. Therecommended method of creation is to drag the nodes from the Paletteto the Process Flowsheet.
6 Calculations 103
6 Define the design constraints on Mach number, noise, etc. for the firstscenario using the Scenario Manager. To access this dialog box, in theBuild group on the Home tab, click Scenarios.
7 Define the pipe network (common to all scenarios). If the network is to besized, some care must be taken in defining reasonable estimates for thepipe diameters.
8 Add the next scenario by clicking Add on the Scenario Manager. Thedata for the sources should be cloned from the previously defined scenariothat has the most similar data. Edit the design constraints of this scenarioif necessary.
9 Make the new scenario current. Highlight it on the Scenario Managerand click Current.
10 Edit the source data for each source for the new scenario. Double-clicksources on the Process Flowsheet.
11 Repeat steps 8 through 10 for all scenarios.
Calculation SpeedCalculation time will often be only a small percentage of the time taken toconstruct the computer model. However, on low specification personalcomputers, a sizing calculation for a complex multiple scenario model couldtake several hours, if not days, when care is not taken in the selection of thethermodynamic models or in the definition of the component slate.
When considering the desired accuracy for the calculations, due considerationmust be given to the fact that you are modeling a system that will rarelycome close to a steady state condition, with a steady state modeling tool.
Component Slate
As a rule of thumb you can assume that the calculation time is proportional tothe square of the number of components. This is especially true when theVLE is calculated by an equation of state instead of treating the fluids as asimple compressible gas.
Flare systems generally operate at conditions in which heavy componentssuch as hexane or heavier will stay in the liquid phase throughout the system.You should therefore endeavor to characterize the heavy ends of petroleumfluids by as few components as possible. The properties that you use for thecharacterization should be optimized to:
Ensure the component stays in the liquid phase.
Match the liquid phase density.
VLE Method
Source compositions may be modeled either by definition of a molecularweight or by a detailed component by component analysis. When acomposition is defined solely by molecular weight, Aspen Flare SystemAnalyzer analyzes the user defined component slate to select a pair ofcomponents whose molecular weights straddle the defined value. A binarycomposition is then calculated to match this value. This type of fluidcharacterization is only suitable for network analyses in which the fluids are
104 6 Calculations
assumed to be vapor, since the VLE behavior cannot be reasonably predictedfrom this level of detail. Thus the Compressible Gas VLE method is the onlyone that should ever be used in association with molecular weight modeling.
When modeling using a detailed component by component analysis, if you areconfident that the system will be liquid free, then the Compressible Gas VLEmethod should be used since it does not have the overhead of determiningthe vapor/liquid equilibrium split. The computation time for the fluidproperties then becomes several orders of magnitudes faster that thoseinvolving a liquid phase.
When modeling a system in which two phase effects are important,consideration must be given to the pressures both upstream of the sourcesand within the flare piping. The Vapor Pressure VLE method, which is thefastest of the multiphase methods, is, strictly speaking, only valid forpressures below 10 bar. The reduced temperature of the fluid should also begreater than 0.3. Experience has shown that it also works to an acceptabledegree of accuracy for flare system analysis at pressures well beyond this. Ifspeed is an issue, it is recommended that a scenario with as many activesources as possible be rated both using one of the cubic equations of stateand this method. If acceptable agreement between the results is achieved, itmay be reasonably assumed that the extrapolation is valid.
Sizing CalculationsThe final calculations upon which a flare system is built should of course bemade using the most detailed model consistent with the quality of dataavailable, but for initial sizing calculations, a number of points should beconsidered when selecting appropriate calculation methods.
There is not generally a great deal of difference between the pressuredrops calculated for a two phase system, whether calculated bytreating the system as a compressible gas or as a two phase fluid. Thisoccurs since the fluid condenses the velocities will decrease while thetwo-phase friction factor will increase.
Unless choked flow is allowed in the system, the back pressure oneach source should not vary greatly with line size. The specification ofa reasonable fixed downstream temperature for each source to beused with the ideal gas enthalpy model should therefore givereasonable results.
The recommended procedure for performing sizing calculations is as follows:
1 Build the network using reasonable estimates for the pipe diameters.Estimate the diameters from:
PM
Wd
300
d = Diameter (m)
W = Mass flow (kg/s)
P = Tip pressure (bar abs)
M = Design mach number
6 Calculations 105
2 Rate the network for all the scenarios with your desired detailed model forthe VLE and enthalpies. This will give reasonable temperaturesdownstream of each source.
3 Copy the calculated temperatures downstream of each source to thesource data by selecting Refresh Source Temperatures from SourceTools in the Tools group on the Home tab of the Ribbon.
4 Size the network for all scenarios using Compress Gas VLE and IdealGas enthalpies.
5 Rate the network for all the scenarios with your desired detailed model forthe VLE and enthalpies. If there are any design violations, make adebottlenecking calculation with these methods.
106 6 Calculations
7 Databases 107
7 Databases
This section provides information on the following topics:
Overview
Database Features
Setting the Password
Pipe Schedule Database Editor
Fittings Database Editor
Component Database Editor
OverviewThe data for the various installable components of the model are stored inuser-modifiable database files.
The database files are:
PIPE_SCHEDULE.MDB - The pipe schedule database. This containsdata for both carbon steel and stainless steel pipe.
FITTINGS.MDB - The pipe fittings database.
COMPONENTS.MDB - The pure component database.
These files are initially installed to the Database sub-directory in your AspenFlare System Analyzer working directory.
Note: You may add and edit your own data to the databases. However, youcannot edit or delete any of the original data.
The databases may be password protected by a single password common toeach. If the password has been disabled, or an incorrect access password hasbeen entered, the databases may be reviewed in read-only mode. You musthave defined an access password before any database can be edited.
Note: Original data is always read-only.
108 7 Databases
Database FeaturesThe Navigation Pane and tabbed environment provide a new user friendly wayto navigate and view simultaneously multiple results and input views. Inputand Results open in a tabbed environment like Microsoft Internet Explorer. Allthe windows are dockable allowing you to organize and customize theworkspace.
Grid ControlsThe data view is supported with rich grid controls for all input and resultviews. The grid controls permit you to sort, custom filter on every columnfield. With filtering, you can restrict the data and choose to view only thosethat want to see.
To access the filters in the data grid, click the filter icon in the columnheader to display a list in which you can choose from.
You may use the following pre-defined auto filters:
Blanks
NonBlanks
Above Average
Below Average
Top 10
Top 10 percentile
Bottom 10
Bottom 10 percentile
If you need to add a custom filter, select Custom from the list. The CustomFilter Selection window is displayed.
You need to add and edit the Operator and Operand in the table, thengroup them with logical conjunction and disjunction to setup a custom filter.The following buttons are available:
Button Description
Add Condition Add a condition in the table. You need to choose a proper Operator,and then input a value for the Operand to complete the newcondition.
RemoveCondition (s)
Remove one or more previously added conditions. Press Ctrl to selectmultiple rows in the table.
Group Selected
'And' Group Group the selected conditions and perform the logical AND operationfor the group. Multiple conditions need to be selected before thisbutton is activated.
'Or' Group Group the selected conditions and perform the logical OR operationfor the group. Multiple conditions need to be selected before thisbutton is activated.
Toggle Toggle the selected logical groups between the logical operationsAND and OR.
7 Databases
Button
Ungroup
A logical formula is displayed under the table toconditions added. Click
Maneuvering Through the TableClick the table to select a record, and then navigate through thethe navigator and scroll bar controls.
Fig 7.1
PrintingClick Print All to print the pipe schedule, fittings or component data,depending on which editor you are currently using. Aspen Flare SystemAnalyzer prints format
Adding/Deleting DataWhen Add is clicked,the last record on the table. You shoulddata.
1. When you add items, they will then become immediately available to thesimulation.
2. Click Delete
Description
Upgroup the selected conditions.
A logical formula is displayed under the table to show the relation for all theconditions added. Click OK to apply the custom filter.
Maneuvering Through the TableClick the table to select a record, and then navigate through thethe navigator and scroll bar controls.
to print the pipe schedule, fittings or component data,depending on which editor you are currently using. Aspen Flare SystemAnalyzer prints formatted output using the default printer settings.
Adding/Deleting Datais clicked, a new record that contains dummy data is inserted as
the last record on the table. You should override this data with your actual
When you add items, they will then become immediately available to the
to delete the current record.
109
show the relation for all the
Click the table to select a record, and then navigate through the table using
to print the pipe schedule, fittings or component data,depending on which editor you are currently using. Aspen Flare System
ted output using the default printer settings.
a new record that contains dummy data is inserted asoverride this data with your actual
When you add items, they will then become immediately available to the
110
Note: You can only delete your own data.
3. Click OK to confirm
Setting The PasswordTo set or modify the password:
Select Set Passwordclicking the aspenONE button on the upper left corner of the applicationwindow.
The Password Editor
Fig 7.2
If you have already set your password, you first need to enter the existingpassword before supplying the new one.
1. Enter your existing password in the
2. Enter your new password in both thePassword boxes,
Pipe Schedule Database EditorThe Pipe Schedule Database Editordata for all pipes in the database, and to add and edit user
1 To use the Pipe Schedule Database EditorDatabase Editoryou enter the password, tbe displayed.
You can only delete your own data.
confirm the update for database.
Setting The PasswordTo set or modify the password:
Set Password from the Application Menu that can be opened byclicking the aspenONE button on the upper left corner of the application
ord Editor window will now be displayed.
If you have already set your password, you first need to enter the existingpassword before supplying the new one.
Enter your existing password in the Old Password box.
Enter your new password in both the New Password andboxes, and then click OK. Click Cancel to abort the procedure.
Pipe Schedule Database EditorPipe Schedule Database Editor allows you to view the pipe schedule
s in the database, and to add and edit user-defined entries.
Pipe Schedule Database Editor, select Pipe ScheduleDatabase Editor from the Databases tab on the Navigation Paneyou enter the password, the Pipe Schedule Database Editor
7 Databases
that can be opened byclicking the aspenONE button on the upper left corner of the application
If you have already set your password, you first need to enter the existing
and Confirm Newto abort the procedure.
Pipe Schedule Database Editorallows you to view the pipe schedule
defined entries.
Pipe Schedulen the Navigation Pane. After
Pipe Schedule Database Editor view will
7 Databases
Fig 7.3
2 If you have already set your password, you will need to enter thepassword before accessing the databases.
3 Select the mateither Carbon
The Nominal Diameterand Group for each entry are tabulated.
The database can be modified by either adding or deAdd or Delete, respectively. Clickprinter defined in thePage Setup in the
For information on the Database view feaSchedule, Fittings and Components Databases, see
If you have already set your password, you will need to enter thepassword before accessing the databases.
Select the material you want to view from the Material list. This may beCarbon Steel or Stainless Steel.
Diameter, Schedule, Internal Diameter, Wall Thicknessfor each entry are tabulated.
The database can be modified by either adding or deleting the entries using, respectively. Click Print All to print the database to the
printer defined in the Page Setup dialog box that can is openedin the Print Preview window.
For information on the Database view features that are common to the PipeSchedule, Fittings and Components Databases, see Database Features
111
If you have already set your password, you will need to enter the
list. This may be
Wall Thickness
leting the entries usingto print the database to the
dialog box that can is opened from File |
tures that are common to the PipeDatabase Features.
112
Fittings Database EditorThe Fittings Database Editorfittings types in the database, and to add and edit user
To display the Fittings Database Editorfrom the Databasepassword, the Fittings D
Fig 7.4
The description of each fitting, as well as the A and B term in the pipe fittingequation is tabulated. The Reference defines the literature source for thedata.
The pipe fitting equation is:
tBFAK
For information on the Database view features that are common to the PipeSchedule, Fittings and Components Databases, see
Component Database EditorThe Component Datfor all the pure components in the database, and to add and edit userentries.
Fittings Database EditorFittings Database Editor allows you to view the pipe fitt
fittings types in the database, and to add and edit user-defined entries.
Fittings Database Editor, select Fittings Database EditorDatabases tab on the Navigation Pane. After you enter the
Fittings Database Editor will be displayed.
The description of each fitting, as well as the A and B term in the pipe fittingequation is tabulated. The Reference defines the literature source for the
The pipe fitting equation is:
For information on the Database view features that are common to the PipeSchedule, Fittings and Components Databases, see Database Features
Component Database EditorComponent Database Editor allows you to view the component data
for all the pure components in the database, and to add and edit user
7 Databases
allows you to view the pipe fittings data for alldefined entries.
Database Editor. After you enter the
The description of each fitting, as well as the A and B term in the pipe fittingequation is tabulated. The Reference defines the literature source for the
For information on the Database view features that are common to the PipeDatabase Features.
Component Database Editorallows you to view the component data
for all the pure components in the database, and to add and edit user-defined
7 Databases
To display the Component Database EditorDatabase Editorenter the password, the
Fig 7.5
The data for each component in the database is tabulated.
For information on the Database view features that are common to the PipeSchedule, Fittings and Componen
Importing Component DataAdditional components may be added to the database via an ASCII file whoseformat is given in
Component Database Editor, select ComponentDatabase Editor from the Database tab on the Navigation Paenter the password, the Component Database Editor will be displayed.
The data for each component in the database is tabulated.
For information on the Database view features that are common to the PipeSchedule, Fittings and Components Databases, see Database Features
Importing Component DataAdditional components may be added to the database via an ASCII file whoseformat is given in Appendix A – File Format.
113
Componentstab on the Navigation Pane. After you
will be displayed.
For information on the Database view features that are common to the PipeDatabase Features.
Additional components may be added to the database via an ASCII file whose
114 7 Databases
8 Automation 115
8 Automation
This section provides information on the following topics:
Overview
Objects
Aspen Flare System Analyzer Object Reference
Example
Updating Automation Files From Previous Versions
OverviewAutomation, defined in its simplest terms, is the ability to drive oneapplication from another. For example, the developers of Product A havedecided in their design phase that it would make their product more usable ifthey exposed Product A’s objects, thereby making it accessible to automation.Since Products B, C and D all have the ability to connect to the applicationthat have exposed objects, each can programmatically interact with productA.
The exposure of its objects makes Aspen Flare System Analyzer a verypowerful and useful tool in the design of hybrid solutions. Since access to anapplication through Automation is language-independent, anyone who canwrite code in Visual Basic, C++ or Java, to name three languages, can writeapplications that will interact with Aspen Flare System Analyzer. There are anumber of applications that can be used to access Aspen Flare SystemAnalyzer through Automation, including Microsoft Visual Basic, Microsoft Exceland Visio. With so many combinations of applications that can transferinformation, the possibilities are numerous and the potential for innovativesolutions is endless.
116 8 Automation
ObjectsThe key to understanding Automation lies in the concept of objects. An objectis a container that holds a set of related functions and variables. InAutomation terminology, the functions of an object are called Methods andthe variables are called Properties. Consider the example of a simple car. Ifit were an object, a car would have a set of properties such as; make, color,engine, etc. The car object might also have methods such as; drive, refuel,etc. By utilizing the properties and methods of the car object it is possible todefine, manipulate and interact with the object.
Fig 8.1
Each property of the car is a variable that has a value associated with it. Thecolor could be either a string or a hexadecimal number associated with aspecific color. The gas mileage could be a floating-point value. Methods arenothing more than the functions and subroutines associated with the object.
An object is a container that holds all the attributes associated with it. Anobject can contain other objects that are a logical subset of the main object.The car object might contain other objects such as engine or tire. Theseobjects have their own set of independent properties and methods. An enginecan have properties related to the number of valves and the size of thepistons. The tires would have properties such as the tread type or modelnumber.
Object HierarchyThe path that is followed to get to a specific property may involve severalobjects. The path and structure of objects is referred to as the objecthierarchy. In Visual Basic the properties and methods of an object areaccessed by hooking together the appropriate objects through a dot operator(.) function. Each dot operator in the object hierarchy is a function call. Inmany cases it is beneficial to reduce the number of calls by settingintermediate object variables.
For instance, expanding on our previous example involving the car, supposethere exists an object called Car and you wish to set the value of its enginesize. You could approach the problem in one of two ways.
Direct specification of object property
Car.Engine.Size = 3
Indirect specification of object property
8 Automation 117
Dim Eng1 as Object
Set Eng1 - Car.Engine.Size
Eng1 = 3
If the Engine size is a property that you wish to access quite often in yourcode, using the indirect method of specification might be easier as it reducesthe amount of code thereby reducing the possibility of error.
The Aspen Flare System Analyzer TypeLibraryIn order to do anything with objects it is first necessary to know what objectsare available. When an application is exposed to Automation, a separate file isusually created that lists all the objects and their respective properties andmethods. This file is called the type library and nearly all programs thatsupport Automation have one of these files available. With the help of anObject Browser, such as the one built into Microsoft Excel, you now have away to view all the objects, properties, and methods in the application byexamining the type library. For Aspen Flare System Analyzer, the type libraryis contained within the file AspenTech.FlareSystemAnalyzer.Interfaces.dll.
The Aspen Flare System Analyzer type library reveals numerous objects thatcontain many combine properties and methods. The type library shows theassociated properties and methods for every object, and returns type forevery property. The type library shows what types of arguments are requiredand what type of value might be returned for every method.
Accessing a specific property or method is accomplished in a hierarchicalfashion by following a chain of exposed objects. The first object in the chain isan object from which all other objects can be accessed. This object willtypically be the main application. In Aspen Flare System Analyzer, thestarting object is the Application object. All other objects are accessible fromthis starting object.
Object BrowserThe type library itself does not exist in a form that is immediately viewable toyou. In order to view the type library, you require the use of an applicationcommonly referred to as an Object Browser. The Object Browser willinterpret the type library and display the relevant information. Microsoft Exceland Visual Basic both include a built in Object Browser.
Accessing the Object Browser in Excel for V7.3Onwards1 Press <Left Alt><F11> or select Visual Basic Editor from Macro group
in the Tools menu (For Excel 2007 or later, please select Visual Basic inthe Code group on the Developer tab).
2 Within the Visual Basic Editor, choose References from the Tools menu.
3 Select the box next to AspenTech.FlareSystemAnalyzer.Interfaces. Ifthis is not displayed, use Browse to locateAspenTech.FlareSystemAnalyzer.Interfaces.dll.
118
4 Click OK.
5 Choose Object Browser
6 Click the arrow in the box at the upper left of the window, and then sAspenTech.FlareSystemAnalyzer
Example: Navigating through the type library
This example shows how to navigate through tdetermine the object hierarchy necessary to access a particular property. Thedesired property is the mass flow of a relief valve called “PSV 1” in thecurrently active scenario.
The first step is to start with the starting objeFlare System Analyzer is always the
Fig 8.2
Selecting the Applicationproperties and methods. Examination of the list of properties does not reveala relief valve object so access to a particular relief valve must be throughanother object. The properties that are links to other objects can bedetermined by looking at the type shown when a property is selected. If thetype is not Stringmost likely an object. The object type shown will be found somewhere in theobject list and the next step is to determine the object hierarchy.
With prior experience in Aspen Flare System Analyzer, theobject is a logical choice.
Object Browser from the View menu or press <F2>.
arrow in the box at the upper left of the window, and then sFlareSystemAnalyzer.Interfaces.dll from the list.
Example: Navigating through the type library
This example shows how to navigate through the type library in order todetermine the object hierarchy necessary to access a particular property. Thedesired property is the mass flow of a relief valve called “PSV 1” in thecurrently active scenario.
The first step is to start with the starting object that in the case of AspenFlare System Analyzer is always the Application object.
Application object in the browser reveals all of its relatedproperties and methods. Examination of the list of properties does not reveal
valve object so access to a particular relief valve must be throughanother object. The properties that are links to other objects can bedetermined by looking at the type shown when a property is selected. If the
String, Boolean, Variant, Double, Integer or Longmost likely an object. The object type shown will be found somewhere in theobject list and the next step is to determine the object hierarchy.
With prior experience in Aspen Flare System Analyzer, the ReliefValvesa logical choice.
8 Automation
<F2>.
arrow in the box at the upper left of the window, and then selectfrom the list.
Example: Navigating through the type library
he type library in order todetermine the object hierarchy necessary to access a particular property. Thedesired property is the mass flow of a relief valve called “PSV 1” in the
ct that in the case of Aspen
object in the browser reveals all of its relatedproperties and methods. Examination of the list of properties does not reveal
valve object so access to a particular relief valve must be throughanother object. The properties that are links to other objects can bedetermined by looking at the type shown when a property is selected. If the
Long then it ismost likely an object. The object type shown will be found somewhere in theobject list and the next step is to determine the object hierarchy.
ReliefValves
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Fig 8.3
The ReliefValvessimple object that is a collection of other objects with some properties andmethods for navigation through the collection.
Fig 8.4
The Item properIReliefValve, The argument named “What” is of type Variant which is thedefault argument type for an argument unless otherwise specified. Allcollection objects within Aspen Flare System Analyzer allow accessindividual member of the collection either by index number (like an array) or
ReliefValves object is shown to be of type IReliefValve. This object is asimple object that is a collection of other objects with some properties andmethods for navigation through the collection.
property is shown to return an indexed object of type, The argument named “What” is of type Variant which is the
default argument type for an argument unless otherwise specified. Allcollection objects within Aspen Flare System Analyzer allow accessindividual member of the collection either by index number (like an array) or
119
. This object is asimple object that is a collection of other objects with some properties and
ty is shown to return an indexed object of type, The argument named “What” is of type Variant which is the
default argument type for an argument unless otherwise specified. Allcollection objects within Aspen Flare System Analyzer allow access to anindividual member of the collection either by index number (like an array) or
120
directly by name. Named arguments are case insensitive so “PSV 1” is thesame as “psv 1”. Either approach is equally valid.
Examining the IReliefValvePropertyByName
Fig 8.5
This property is a read/write property that is used to access all data for arelief valve.
The argument is a case insensitive string that describes the variable that wewish to access. In thlist of property names for each type of object is given at the end of thischapter.
The resulting syntax to access the desired property is:
ReliefValves.Item(“PSV1”).PropertyByName(“MassFlow”)
Automation Syntax
Declaring Objects
An object in Visual Basic is another type of variable and should be declared.Objects can be declared using the generic type identifierpreferred method however uses the type library reference to declare theobject variables by an explicit object name.
Early Binding:
Dim | Public | Privatelibrary
Late Binding:
directly by name. Named arguments are case insensitive so “PSV 1” is thesame as “psv 1”. Either approach is equally valid.
IReliefValve object type shows a property calledPropertyByName, which is type Variant.
This property is a read/write property that is used to access all data for a
The argument is a case insensitive string that describes the variable that wewish to access. In this case this string would have the valve “MassFlow”. A fulllist of property names for each type of object is given at the end of this
The resulting syntax to access the desired property is:
ReliefValves.Item(“PSV1”).PropertyByName(“MassFlow”)
omation Syntax
Declaring Objects
An object in Visual Basic is another type of variable and should be declared.Objects can be declared using the generic type identifier objectpreferred method however uses the type library reference to declare the
ect variables by an explicit object name.
| Public | Private Objectvar as ObjectName as specified in the type
8 Automation
directly by name. Named arguments are case insensitive so “PSV 1” is the
property called
This property is a read/write property that is used to access all data for a
The argument is a case insensitive string that describes the variable that weis case this string would have the valve “MassFlow”. A full
list of property names for each type of object is given at the end of this
An object in Visual Basic is another type of variable and should be declared.object. The
preferred method however uses the type library reference to declare the
ObjectName as specified in the type
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Dim | Public | Private objectvar as Object
Once a reference to a type library has been established, the actual name ofthe object as it appears in the type library can be used. This is called earlybinding. It offers some advantages over late binding, including speed andaccess to Microsoft’s IntelliSense functionality when using Visual Basic orVBA.
Example: Object Declaration
Early Binding:
Public fnApp as Object
Public thisPsv as Object
Late Binding:
Public fnApp as AspenTech.FlareSystemAnalyzer.Interfaces.Application
Public thisPsv as AspenTech.FlareSystemAnalyzer.Interfaces.IReliefValve
The Set Keyword
Syntax:
Set objectvar = object.[object...].object | Nothing
Connections or references to object variables are made by using the Setkeyword.
Example: Set
Assuming fnApp is set to the Application Object
Dim thisPsv as AspenTech.FlareSystemAnalyzer.Interfaces.IReliefValve
Set thisPsv - fnApp.ReliefValves.item(1)
CreateObject, GetObject
Syntax for creating an instance of an application:
CreateObject (class)
GetObject ([pathname] [,class])
Where class is the starting object as specified in the type library.
In order to begin communication between the client and server applications,an initial link to the server application must be established. In Aspen FlareSystem Analyzer this is accomplished through the starting objectApplication.
The CreateObject function will start a new instance of the main application.CreateObject is used in Aspen Flare System Analyzer with theAspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application class as defined in the type library. This connects to themain application interface of Aspen Flare System Analyzer.
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Example: CreateObject
Dim FnApp As Object
Set FnApp = CreateObject(“AspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application”)
The following example uses early binding in the object declaration to createan instance of Aspen Flare System Analyzer and then load a specified model.
Example: CreateObject
Dim FnApp AsAspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application
Set FnApp = CreateObject(“AspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application”)
FnApp.OpenModel “c:\Aspen Flare System Analyzer<version>\Samples\Ole\Excel\olesample.fnw”
The GetObject function will connect to an instance of the server applicationthat is already running. If an instance of the application is not already runningthen a new instance will be started.
Object Properties, Methods and Hierarchy
Syntax for creating and accessing properties:
Set objectvar = object.[object.object...] .object
Variable = object.[object.object...] .object.property
Syntax for accessing methods:
Function Method
returnvalue = object.method ([argument1, argument2, ...])
Subroutine method
object.method argument1, argument2, ...
The sequence of objects is set through a special dot function. Properties andmethods for an object are also accesses through the dot function. It ispreferable to keep the sequences of objects to a minimum since each dotfunction is a call to a link between the client and the server application.
The object hierarchy is an important and fundamental concept for utilizingautomation. A particular property can only be accessed by following a specificchain of objects. The chain always begins with the Application object andends with the object containing the desired property.
The methods of objects are accessed in the same fashion as properties byutilizing the dot function. A method for a particular object is nothing morethan a function or subroutine whose behavior is related to the object in somefashion.
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Typically the methods of an object will require arguments to be passed whenthe method is called. The type library will provide information about whicharguments are necessary to call a particular method. A function will return avalue.
Note: Subroutines in Visual Basic do not require parentheses around theargument list.
Examples: Accessing Aspen Flare SystemAnalyzer Object PropertiesDim FnApp AsAspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application
Dim SepDiam as Double
Set FnApp = CreateObject(“AspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application”)
FnApp.OpenModel “c:\Aspen Flare System Analyzer<version>\Samples\Ole\Excel\olesample.fnw”
SepDiam - FnApp.HorizontalSeparators.Item[1].PropertyByName(“Diameter”)
This example starts up Aspen Flare System Analyzer and opens a specificcase. The diameter of a specific horizontal separator is then obtained. Thediameter is obtained through a connection of the Application andHorizontalSeparators objects.
Dim FnApp AsAspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application
Dim Seps asAspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.IHorizontalSeparators
Dim Sep asAspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.IHorizontalSeparator
Dim SepDiam as Double
Set FnApp = CreateObject(“AspenTech.FlareSystemAnalyzer.InterfacesAspenTech.FlareSystemAnalyzer.Interfaces.Application”)
FnApp.OpenModel “c:\Aspen Flare System Analyzer<version>\Samples\Ole\Excel\olesample.fnw”
Set Seps = FnApp.HorizontalSeparators
Set Sep = Seps.Item[I]
SepDiam = Sep.PropertyByName (“Diameter”)
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This example also gets the diameter of a specific horizontal separator, butcreates all the intermediate objects so that when the diameter value isactually requested the chain of objects only contains one object.
Collection Objects
Syntax: Properties of a Collection Object:
Item(Index) -- Accesses a particular member of the collection by nameor number
Count -- Returns the number of objects in the collection
Syntax: Enumeration of Objects:Dim Element as ObjectDim iElement as LongDim nElements as LongFor iElement=1 to nElementsSet Element = FnApp.Elements.Item(iElement)
[statements]
Next [element]
A collection object is an object that contains a set of other objects. This issimilar to an array of objects. The difference between an array of objects anda collection object is that a collection object is that a collection object containsa set of properties and methods for manipulating the objects in the collection.The Count property returns the number of items in the collection and theItem property takes an index value or name as the argument and returns areference to the object within the collection.
Examples: Accessing Collection Objects
Dim myPsvs as AspenTech.FlareSystemAnalyzer.Interfaces.IReliefValves
Dim name as String
Dim i As Integer
Set myPsvs = myApp.ReliefValves
For i = 1 To myPsvs.Count
name = myPsvs.Item(i).PropertyByName(“Name”)
MsgBox name
Next i
This example connects to a collection of relief valves by setting the myPsvsobject. A For loop is created that uses the Count and item properties of acollection in order to display a message box that display the name of eachrelief valve in turn. The items in the collection are indexed beginning at 1. Theapplication object is assumed to have been already set to myApp.
Variants
Syntax: Using variant values:
8 Automation 125
Dim myvariant as Variant
myvariant = [object.property]
To determine the upper and lower bound of the variant:
UBound(arrayname[,dimension])
LBound(arrayname[,dimension])
A property can return a variety of variable type. Values such asTemperature or Pressure are returned as Doubles or 32-bit floating pointvalues. The Name property returns a String value. Visual Basic provides anadditional variable called Variant. A Variant is a variable that can take onthe form of any type of variable including Integer, Long, Double, String,Array, and Objects.
If the property of an object returns an array whose size can vary dependingupon the case, then a Variant is used to access that value. For example, theComposition property of a ControlValve returns an array of Doubles sizedto the number of components in the model.
In Visual Basic, if a variable is not explicitly declared then it is implicitly aVariant. Variants have considerably more storage associated with their useso for a large application it is good practice to limit the number of Variantsbeing used. It is also just good programming practice to explicitly declarevariables whenever possible.
Example: Using Variants in Aspen Flare SystemAnalyzer
Dim myPsvs as AspenTech.FlareSystemAnalyzer.Interfaces.IReliefValve
Dim molefracs as Variant
Dim i As Integer
Set myPsv = myApp.ReliefValves.Item(1)
molefracs = myPsv.PropertyByName (“Composition”)
For i = LBound(molefracs) To Ubound (molefracs)
Debug.Print molefracs(i)
Next i
This example shows how to get the mole fractions of a relief valve for thecurrent scenario. The values are sent to the Visual Basic Immediate window.The application object is assumed to have been already set to myApp.
Unknown Values
There are a number of occasions where a variable may be unknown such asall the calculated values prior to the calculation or the flange size of a controlvalve. In all cases this is represented by the valuefntVariableStatus_fntUnknownValue.
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Example: Using Unknown Values in Aspen FlareSystem Analyzer
Dim myValve as AspenTech.FlareSystemAnalyzer.Interfaces.IControlValves
Dim myValves as AspenTech.FlareSystemAnalyzer.Interfaces.IControlValve
Dim flange as Double
Dim name as String
Set myValves = myApp.ControlValves
For i=1 to myValves.Count
flange = myValves.Item(i).PropertyByName (“FlangeDiameter”)
If flange = fntVariableStatus_fntUnknownValue Then
name = myValve.PropertyByName(“Name”)
MsgBox name
EndIf
Next i
This example loops through all the control valves and displays the name ofany whose flange diameter is unknown. The application object is assumed tohave been already set to myApp.
Aspen Flare System AnalyzerObject ReferenceThe following subsections summarize the methods and properties available foreach object available within Aspen Flare System Analyzer. They are orderedpurely alphabetically.
For each object the attributes comprise the type (or class) of object followedby the access characteristics which may be read-only or read/write. Ingeneral, data has the read/write attribute and calculated values have theread-only attribute.
Each method is shown with the method name including any arguments, adescription of the method and a description of the arguments.
Each property is shown with the property name including any arguments, adescription of the property, the property attributes and a description of thearguments. Optional arguments are shown in square brackets [].
Many objects support a PropertyByName property. In such cases a furthertable gives the valid property names which are case insensitive as well as theproperty attributes and the units of measure where appropriate. The propertynames will generally match the field descriptions on the corresponding viewsbut they never contain any space characters.
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ApplicationDescription : Application object
Methods
Name Description Arguments
OpenModel(fileName AsString)
Open an Aspen FlareSystem Analyzer model
fileName = Model filename
SaveModel(fileName AsString)
Save an Aspen FlareSystem Analyzer model
fileName = Model filename
DoImport(imType AsimportType, source AsString, Definition AsString, Flag As Reserved)As Integer
Import an Aspen FlareSystem Analyzer Model
imType = 0,1,2 forxml,xls,mdb files
source = Import filename
Definition = Definition filename
Flag = 0
DoExport(exType AsexportType, source AsString, Definition AsString, Flag As Reserved)As Integer
Export an Aspen FlareSystem Analyzer Model
exType = 0,1,2 for xml, xls,mdb files
source = Export filename
Definition = Definition filename
Flag = 0
LaunchFlarenet([fileNameAs String])
Display the Aspen FlareSystem Analyzerapplication window
fileName = Model filename
Quit() Quit Aspen Flare SystemAnalyzer.
Please call this method beforeyour scripts end.
Note: The LaunchFlarenet method only launches the Aspen Flare SystemAnalyzer Graphical User Interface (GUI) in a separate process which cannotbe controlled directly. The Quit method cannot terminate the GUI opened bythe LaunchFlarenet method.
Properties
Name Description Attributes Arguments
Bleeds Collection of flow bleedobjects
IBleeds, read-only
Components Collection of componentobjects
IComponents,read-only
Connectors Collection of connectorobjects
IConnectors,read-only
ControlValves Collection of control valveobjects
IControlValves,read-only
HorizontalSeparators
Collection of horizontalseparator objects
IHorizontalSeparators,read-only
Nodes Collection of node objects INodes, read-only
OrificePlates Collection of orifice plateobjects
IOrificePlates,read-only
Pipes Collection of pipe objects IPipes, read-only
ReliefValves Collection of relief valveobjects
IReliefValves,read-only
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Name Description Attributes Arguments
Scenarios Collection of scenario objects IScenarios, read-only
Solver Solver object ISolver, read-only
Tees Collection of tee objects ITees, read-only
Tips Collection of flare tip objects ITips, read-only
VerticalSeparators Collection of verticalseparator objects
IVerticalSeparators, read-only
BleedDescription : Flow bleed object
Attributes : IBleed, read-only
Methods
Name Description Arguments
Connect(ConnectionIdx AsfntNodeEnd, Pipe As IPipe,PipeConnectionIdx AsfntPipeEnd)
Connect to a pipe ConnectionIdx = Connectionon bleed
Pipe = Pipe to connect to
PipeConnectionIdx =Connection on pipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect from apipe
ConnectionIdx = Connectionon bleed
Properties
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for anamed property
Variant, read/write What = Propertyname
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Ignored fntYesNo, read/write
Location String, read/write
Name String, read/write
OfftakeMaximum kg/hr Double, read/write
OfftakeMinimum kg/hr Double, read/write
OfftakeMultiplier Double, read/write
OfftakeOffset kg/hr Double, read/write
PressureDrop bar Double, read/write
BleedsDescription : Collection of flow bleed objects
Attributes : IBleeds, read-only
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Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a newbleed
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete (What) Delete a bleed What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items in thecollection
Long, read-only
Item(What)
Indexed item in thecollection
IBleed, read-only
What = Index as Name(String) or Number(Integer/Long)
ComponentDescription : Component object
Attributes : IComponent, read-only
Methods
Name Description Arguments
Clear (Optional CnamecompName As String= Nothing)
Clear all component data Cname = ComponentName. If omitted allcomponents will becleared.
EstimateUnknown Estimate all unknown component data
Properties
Name Description Attributes Arguments
IsValid Validate componentdata is complete
Boolean, read-only
PropertyByName(What As String)
Property value for anamed property
Variant, read/write What = Propertyname
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
AcentricFactor Double, read/write
AcentricFactorSrk Double, read/write
CharacteristicVolume m3/kgmole Double, read/write
CriticalPressure bar abs Double, read/write
CriticalTemperature K Double, read/write
130 8 Automation
Name Units Attributes
CriticalVolume m3/kgmole Double, read/write
EnthalpyCoefficients kJ/kgmole
kJ/kgmole/K
kJ/kgmole/K2
kJ/kgmole/K3
kJ/kgmole/K4
kJ/kgmole/K5
Double(1 To 6), read/write
EntropyCoefficient Double, read/write
Id Integer, read/write
MolecularWeight Double, read/write
Name String, read/write
NormalBoilingPoint K Double, read/write
StandardDensity kg/m3 Double, read/write
Type fntCompType, read/write
WatsonK Double, read/write
ViscosityCoefficient Double(1 To 2), read/write
ComponentsDescription : Collection of component objects
Attributes : IComponents, read-only
Methods
Name Description Arguments
AddLibrary(What AsVariant)
Add a librarycomponent
What = Component identifier aseither name (String) or ID(Integer/Long)
AddHypothetical(WhatAs String)
Add a namedhypothetical component
What = Name for newcomponent
Delete(What) Delete a component What = Index as component aseither Name (String) or Number(Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items inthe collection
Long, read-only
Item(What) Indexed item in thecollection
IComponent,read-only
What = Index as Name(String) Or Number(Integer/Long)
ConnectorDescription : Connector node object
Attributes : IConnector, read-only
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Methods
Name Description Arguments
Connect(ConnectionIdxAs fntNodeEnd, Pipe AsIPipe, PipeConnectionIdxAs fntPipeEnd)
Connect to a pipe ConnectionIdx = Connection onconnector
Pipe = Pipe to connect to
PipeConnectionIdx = Connectionon pipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect from apipe
ConnectionIdx = Connection onconnector
Properties
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Property name
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Angle radians Double, read/write
Ignored fntYesNo, read/write
Length m Double, read/write
Location String, read/write
Name String, read/write
ConnectorsDescription : Collection of connector objects
Attributes : IConnectors, read-only
Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a newconnector
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete (What) Delete a connector What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items in thecollection
Long, read-only
Item(What) Indexed item in thecollection
IConnector, read-only
What = Index asName (String) OrNumber(Integer/Long)
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ControlValveDescription : Control valve object
Attributes : IControlValve, read-only
Methods
Name Description Arguments
Connect(ConnectionIdxAs fntNodeEnd, Pipe AsIPipe, PipeConnectionIdxAs fntPipeEnd)
Connect to a pipe ConnectionIdx = Connection oncontrol valve
Pipe = Pipe to connect to
PipeConnectionIdx = Connectionon pipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect from apipe
ConnectionIdx = Connection oncontrol valve
Properties
Name Description Attributes Arguments
PropertyByName(What As String,
[Scenario])
Property value fora named property
Variant,read/write
What = Property name
Scenario = Scenario Indexas Name (String) orNumber (Integer/Long)
PropertyNames Collection of allthe propertynames
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Composition fractions Double (1 To ?), read/write
CompositionBasis fntCompBasis, read/write
Energy kJ/hr Double, read-only
Enthalpy kJ/kgmole Double, read-only
Entropy kJ/kgmole/K Double, read-only
FlangeDiameter mm Double, read/write
FluidType fntCompType, read/write
Ignored fntYesNo, read/write
Location String, read/write
LockMabp fntYesNo, read/write
Mabp bar abs Double, read-only
MassFlow kg/hr Double, read/write
MolecularWeight Double, read/write
Name String, read/write
OutletMachNumber Double, read-only
OutletSonicVelocity m/s Double, read-only
OutletTemperature C Double, read-only
OutletTemperatureSpecification C Double, read-only
OutletVelocity m/s Double, read-only
ReliefPressure bar abs Double, read-only
StaticOutletPressure bar abs Double, read-only
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Name Units Attributes
StaticInletPipePressureDrop bar Double, read-only
Temperature C Double, read-only
TemperatureSepcification fntTempSpec, read/write
TotalOutletPressure bar abs Double, read-only
TotalInletPipePressureDrop bar Double, read-only
VapourFraction molar fraction Double, read-only
ControlValvesDescription : Collection of control valve objects
Attributes : IControlValves
Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a newcontrol valve
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete a controlvalve
What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items inthe collection
Long, read-only
Item(What) Indexed item in thecollection
IControlValve,read-only
What = Index as Name(String) or Number(Integer/Long)
HorizontalSeparatorDescription : Horizontal separator object
Attributes : IHorizontalSeparator, read-only
Methods
Name Description Arguments
Connect(ConnectionIdxAs fntNodeEnd, Pipe AsIPipe, PipeConnectionIdxAs fntPipeEnd)
Connect to a pipe ConnectionIdx = Connection onhorizontal separator
Pipe = Pipe to connect to
PipeConnectionIdx = Connection onpipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect froma pipe
ConnectionIdx = Connection onhorizontal separator
Properties
134 8 Automation
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for a namedproperty
Variant,read/write
What = Propertyname
PropertyNames Collection of all the propertynames
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Diameter mm Double, read/write
Ignored fntYesNo, read/write
LiquidLevel mm Double, read/write
Location String, read/write
Name String, read/write
HorizontalSeparatorsDescription : Collection of horizontal separator objects
Attributes : IHorizontalSeparators, read-only
Method
Name Description Arguments
Add ([Name AsString],[Xcoordinate AsSingle = 0][Ycoordinate AsSingle = 0])
Add a newhorizontalseparator
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete a horizontalseparator
What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of itemsin the collection
Long, read-only
Item(What) Indexed item inthe collection
IHorizontalSeparator, read-only
What = Index as Name (String)Or Number (Integer/Long)
NodesDescription : Collection of all node objects
Attributes : INodes, read-only
Properties
Name Description Attributes Arguments
Count Number of items in thecollection
Long, read-only
8 Automation 135
OrificePlateDescription : Orifice plate object
Attributes : IOrificePlate, read-only
Method
Name Description Arguments
Connect(ConnectionIdxAs fntNodeEnd, Pipe AsIPipe, PipeConnectionIdxAs fntPipeEnd)
Connect to apipe
ConnectionIdx = Connection onorifice plate
Pipe = Pipe to connect to
PipeConnectionIdx = Connection onpipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect froma pipe
ConnectionIdx = Connection onorifice plate
Properties
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Property name
PropertyNames Variant array of all theproperty names
Variant, read-only
Named Properties For PropertyByName()
Name Units Attributes
Diameter mm Double, read/write
DratioIn Double, read/write
DratioOut Double, read/write
Ignored fntYesNo, read/write
Location String, read/write
Name String, read/write
OrificePlatesDescription : Collection of orifice plate objects
Attributes : IOrificePlates, read-only
Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a neworifice plate
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete an orificeplate
What = Index as Name (String) orNumber (Integer/Long)
Properties
136 8 Automation
Name Description Attributes Arguments
Count Number of items in thecollection
Long, read-only
Item(What)
Indexed item in thecollection
IOrificePlate, read-only
What = Index asName (String) OrNumber(Integer/Long)
PipeDescription : Pipe object
Attributes : IPipe, read-only
Methods
Name Description Arguments
AddFitting(FittingNameAs String, [Count AsLong = 1])
Add a fitting to thefittings list
FittingName = Name offitting defined in the pipefittings database
Count = Number of fittingsof this type to add
Connect(ConnectionIdxas fntPipeEnd, Node AsObject,NodeConnectionIdx asfntNodeEnd)
Connect to a node ConnectionIdx =Connection on pipe
Node = Node to connect to
NodeConnectionIdx =Connection on node
DeleteAllFittings() Delete all fittingsfrom the fittings list
DeleteFittingByIndex(FittingIndex As Long)
Delete a fitting fromthe fittings list
FittingIndex = Index offitting in the fittings list todelete
DeleteFittingByName(FittingName As String,[Count As Long = 1])
Delete a fitting fromthe fittings list
FittingName = Name offitting defined in the pipefittings database
Count = Number of fittingsof this type to delete
Disconnect(ConnectionIdx As fntPipeEnd)
Disconnect from anode
ConnectionIdx =Connection on pipe
GetFittingCount() AsLong
Get number offittings in the fittinglist
GetFittingName(FittingIndex As Long) AsString
Get name of indexedpipe fitting
FittingIndex = Index offitting in the fittings list toretrieve name for
Properties
8 Automation 137
Name Description Attributes Arguments
PropertyByName(What As String,
[Scenario],[Phase],
[PipeEnd])
Property value for anamed property
Variant,read /write
What = Property name
Scenario = Scenario Index asName (String) or Number(Integer/Long)
Phase = Phase Index(fntFluidPhase)
PipeEnd = Pipe end(fntPipeEnd)
PropertyNames Collection of all theproperty names
String, read-only
UseFittings Flag to indicate if afittings list is usedinstead of losscoefficients
Boolean,read/write
Named Properties For PropertyByName()
Name Units Attributes
AccelerationPressureDrop bar Double, read-only
AmbientTemperature C Double, read-only
CanSize fntYesNo, read/write
MoleFractions Double(1 To ?), read-only
Density kg/m3 Double, read-only
Duty kJ/hr Double, read-only
ElevationChange m Double, read/write
ElevationPressureDrop bar Double, read-only
Emissivity Double, read-only
Energy kJ/hr Double, read-only
Enthalpy kJ/kgmole Double, read-only
Entropy kJ/kgmole/K Double, read-only
EquivalentLength m Double, read-only
ExternalDuty W Double, read/write
ExternalHeatTransferCoefficient W/m2/K Double, read-only
ExternalRadiativeHeatTransferCoefficient W/m2/K Double, read-only
ExternalTemperature C Double, read-only
FittingsLossConstant Double, read-only
FittingsLossMultiplier Double, read-only
FittingsPressureDrop bar Double, read-only
FlowRegime fntFlowRegime, read-only
FrictionFactor Double, read-only
FrictionPressureDrop bar Double, read-only
HeatCapacity kJ/kgmole/K Double, read-only
HeatTransfer kJ/hr Double, read-only
Ignored fntYesNo, read/write
IgnoreHeadRecovery fntYesNo, read/write
138 8 Automation
Name Units Attributes
InsulationName String, read/write
InsulationThickness mm Double, read/ write
InsulationThermalConductivity W/m/K Double, read/write
InternalDiameter mm Double, read/write
Length m Double, read/write
LengthMultiplier Double, read/write
Location String, read/write
MachNumber Double, read-only
MassFlow kg/hr Double, read/write
Material fntPipeMaterial,read/write
MolecularWeight Double, read-only
MolarFlow kgmole/hr Double, read-only
Name String, read/write
Noise dB Double, read-only
NominalDiameter String, read/write
OutletTemperatureSpecification C Double, read/write
OverallHeatTransferCoefficient W/m2/K Double, read-only
UsePipeClass fntYesNo, read/write
PhaseFraction Double, read-only
PressureDrop bar Double, read-only
RatedMassFlow kg/hr Double, read-only
ReynoldsNumber Double, read-only
RhoV2 kg/m/s2 Double, read-only
Roughness mm Double, read/write
StaticPressure bar abs Double, read-only
Schedule String, read/write
SurfaceTension dynes/cm Double, read-only
TailPipe fntYesNo, read/write
Temperature C Double, read-only
ThermalConductivity W/m/K Double, read-only
TotalPressure bar abs Double, read-only
VapourFraction molar fraction Double, read-only
Velocity m/s Double, read-only
Viscosity cP Double, read-only
WallThermalConductivity W/m/K Double, read/write
WallTemperature C Double, read-only
WallThickness mm Double, read/write
WindSpeed m/s Double, read/write
Zfactor Double, read-only
PipesDescription : Collection of pipes
8 Automation 139
Attributes : IPipes
Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a newpipe
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete a pipe What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items in thecollection
Long, read-only
Item(What)
Indexed item in thecollection
IPipe, read-only What = Index as Name(String)
or Number (Integer/Long)
ReliefValveDescription : Relief valve object
Attributes : IReliefValve, read-only
Methods
Name Description Arguments
Connect(ConnectionIdx AsfntNodeEnd, Pipe As IPipe,pipeConnectionIdx AsfntPipeEnd)
Connect to apipe
ConnectionIdx = Connection on reliefvalve
Pipe = Pipe to connect to
PipeConnectionIdx = Connection onpipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnectfrom a pipe
ConnectionIdx = Connection on reliefvalve
Properties
Name Description Attributes Arguments
PropertyByName(What As String,
[Scenario])
Property value for anamed property
Variant,read/write
What = Property name
Scenario = ScenarioIndex as Name (String)or Number(Integer/Long)
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Composition fractions Double (1 To ?),read/write
140 8 Automation
Name Units Attributes
CompositionBasis fntCompBasis,read/write
Contingency fntContingency,read/write
Energy kJ/hr Double, read-only
Enthalpy kJ/kgmole Double, read-only
Entropy kJ/kgmole/K Double, read-only
FlangeDiameter mm Double, read/write
FluidType fntCompType,read/write
HemCd Double, read/write
HemLiqCd Double. Read/write
Ignored fntYesNo, read/write
Kb Double, read/write
Location String, read/write
LockMabp fntYesNo, read/write
LockReliefPressure fntYesNo, read/write
LockRatedMassFlow fntYesNo, read/write
Mabp bar abs Double, read-only
MassFlow kg/hr Double, read/write
Mawp bar abs Double, read/write
MechanicalPressure bar abs Double, read/write
MolecularWeight Double, read/write
Name String, read/write
Orifice String, read/write
OutletMachNumber Double, read-only
OutletSonicVelocity m/s Double, read-only
OutletTemperature C Double, read-only
OutletTemperatureSpecification C Double, read-only
OutletVelocity m/s Double, read-only
RatedMassFlow kg/hr Double, read/write
ReliefPressure bar abs Double, read-only
SizingBackPressure Bar abs Double, read/write
SizingMethod Integer, read/write
StaticOutletPressure bar abs Double, read-only
StaticInletPipePressureDrop bar Double, read-only
Temperature C Double, read-only
TemperatureSpecification fntTempSpec,read/write
TotalOutletPressure bar abs Double, read-only
TotalInletPipePressureDrop bar Double, read-only
ValveArea mm2 Double, read/write
ValveCount Integer, read/write
ValveType fntPsvType, read/write
8 Automation 141
Name Units Attributes
VapourFraction molar fraction Double, read-only
ReliefValvesDescription : Collection of relief valve objects
Attributes : IReleifValves
Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a new reliefvalve
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate onthe Process Flowsheet (Twips)
Ycoordinate = Y coordinated onthe Process Flowsheet (Twips)
Delete(What) Delete a relief valve What = Index as Name (String)or Number (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items inthe collection
Long, read-only
Item(What) Indexed item in thecollection
IReliefValve,read-only
What = Index as Name(String) or Number(Integer/Long)
ScenarioDescription : Scenario object
Attributes : IScenario, read-only
Properties
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Property name
PropertyNames Variant array of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
AtmosphericPressure bar abs Double, read/write
Calculate fntYesNo, read/write
HeaderLiquidVelocityLimit m/s Double, read/write
HeaderMachLimit Double, read/write
HeaderNoiseLimit dB Double, read/write
HeaderRhoV2Limit kg/m/s2 Double, read/write
142 8 Automation
Name Units Attributes
HeaderVapourVelocityLimit m/s Double, read/write
Name String, read/write
TailpipeLiquidVelocityLimit m/s Double, read/write
TailpipeMachLimit Double, read/write
TailpipeNoiseLimit dB Double, read/write
TailpipeRhoV2Limit kg/m/s2 Double, read/write
TailpipeVapourVelocityLimit m/s Double, read/write
ScenariosDescription : Collection of scenario objects
Attributes : IScenarios, read-only
Methods
Name Description Arguments
Add([Name AsString],
[CloneIdx AsLong = 1])
Add a new scenario Name = New scenario name
CloneIdx = Index of scenario to copy datafrom for initialization
Delete(What) Delete a scenario What = Index as Name (String) or Number(Integer/Long)
Properties
Name Description Attributes Arguments
Active Set active scenario What = Index as Name(String) or Number(Integer/Long)
ActiveScenario Get active scenario IScenario, read-only
Count Number of items in thecollection
Long, read-only
Item(What) Indexed item in thecollection
IScenario, read-only
What = Index as Name(String) or Number(Integer/Long)
SolverDescription : Solver object
Attributes : ISolver, read-only
Methods
Name Description Arguments
Halt Stop calculations
Start Start calculations
Properties
8 Automation 143
Name Description Attributes Arguments
IsActive Get calculation status Boolean, read-only
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Propertyname
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
AmbientTemperature C Double, read/write
AtmosphericPressure bar abs Double, read/write
CalculationMode fntCalcMode, read/write
CheckChokedFlow fntYesNo, read/write
Elements Integer, read/write
EnableHeatTransfer fntYesNo, read/write
EnthalpyMethod fntEnthMethod,read/write
InitialPressure bar abs Double, read/write
KineticEnergyBasis fntKeBasis, read/write
LengthMultiplier Double, read/write
LoopIteration Integer, read-only
LoopIterationLimit Integer, read/write
LoopTolerance % Double, read/write
PressureDropMethod fntPresDropMethod(0 to2), read/write
PropertyIteration Integer, read-only
PropertyIterationLimit Integer, read/write
PropertyTolerance % Double, read/write
ScenarioMode fntScenarioMode,read/write
UnitOperationTolerance % Double, read/write
UseKineticEnergy fntYesNo, read/write
UseRatedFlow fntYesNo, read/write
VleMethod fntVleMethod,read/write
WindSpeed Double, read/write
TeeDescription : Tee object
Attributes : ITee, read-only
Methods
Name Description Arguments
144 8 Automation
Name Description Arguments
Connect(ConnectionIdx AsfntNodeEnd, Pipe As IPipe,PipeConnectionIdx AsfntPipeEnd)
Connect to a pipe ConnectionIdx =Connection to tee
Pipe = Pipe to connect to
PipeConnectionIdx =Connection on pipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect from a pipe ConnectionIdx =Connection on tee
Properties
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Property name
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Angle fntTeeAngle, read/write
Body fntTeeEnd, read/write
Ignored fntYesNo, read/write
Location String, read/write
Name String, read/write
TeesDescription : Collection of tee objects
Attributes : ITees, read-only
Method
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a new tee Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete a tee What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items inthe collection
Long, read-only
Item(What) Indexed item in thecollection
ITee, read-only What = Index as Name(String) Or Number(Integer/Long)
8 Automation 145
TipDescription : Flare tip object
Attributes : ITip, read-only
Methods
Name Description Arguments
AddCurve() Add a pressure dropcurve
AddCurvePoint(Index As Long) Append a point to apressure drop curve
Index = Index of curve
Connect(ConnectionIdx AsfntNodeEnd, Pipe As IPipe,PipeConnectionIdx AsfntPipeEnd)
Connect to a pipe ConnectionIdx =Connection to tee
Pipe = Pipe to connect to
PipeConnectionIdx =Connection on pipe
DeleteCurve(Index As Long) Delete a pressure dropcurve
Index = Index of curve
DeleteCurvePoint(Index As Long,Which As Long)
Index = Index of curve
Which = Index of point
Disconnect(ConnectionIdx AsfntNodeEnd)
Disconnect from a pipe ConnectionIdx =Connection on flare tip
Properties
Name Description Attributes Arguments
CurveMolWt(Index As Long)
Molecular weight ofindexed pressure dropcurve
Double, read/write Index = Curve index
CurvePointMassFlow(Index AsLong, Which AsLong)
Mass flow of point on apressure drop curve(kg/hr)
Double, read/write Index = Index of curve
Which = Index of point
CurvePointPressureDrop(Index AsLong, Which AsLong)
Pressure drop of pointon a pressure dropcurve (bar)
Double, read/write Index = Index of curve
Which = Index of point
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Property name
PropertyNames Collection of all theproperty names
String, read-only
Named Properties For PropertyByName()
Name Units Attributes
Diameter mm Double, read/write
Ignored fntYesNo, read/write
K Double, read/write
Kbasis fntKbasis, read/write
Location String, read/write
Name String, read/write
Reference Temperature Double, read/write
146 8 Automation
Name Units Attributes
UseCurves fntYesNo, read/write
TipsDescription : Collection of flare tip objects
Attributes : ITips, read-only
Methods
Name Description Arguments
Add ([Name AsString], [XcoordinateAs Single = 0][Ycoordinate As Single= 0])
Add a newflare tip
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete a flaretip
What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items inthe collection
Long, read-only
Item(What) Indexed item in thecollection
ITip, read-only What = Index as Name(String) Or Number(Integer/Long)
VerticalSeparatorDescription : Vertical separator object
Attributes : IVerticalSeparator, read-only
Methods
Name Description Arguments
Connect(ConnectionIdx AsfntNodeEnd, Pipe As IPipe,PipeConnectionIdx AsfntPipeEnd)
Connect to a pipe ConnectionIdx = Connectionon vertical separator
Pipe = Pipe to connect to
PipeConnectionIdx =Connection on pipe
Disconnect(ConnectionIdxAs fntNodeEnd)
Disconnect from apipe
ConnectionIdx = Connectionon vertical separator
Properties
Name Description Attributes Arguments
PropertyByName(What As String)
Property value for anamed property
Variant,read/write
What = Property name
PropertyNames Collection of all theproperty names
String, read-only
8 Automation 147
Named Properties For PropertyByName()
Name Units Attributes
Diameter mm Double, read/write
Ignored Boolean, read/write
Location String, read/write
Name String, read/write
VerticalSeparatorsDescription : Collection of vertical separator objects
Attributes : IVerticalSeparators, read-only
Methods
Name Description Arguments
Add ([Name As String],[Xcoordinate As Single =0] [Ycoordinate As Single= 0])
Add a newverticalseparator
Name: If omitted a new name isautomatically generated
Xcoordinate = X coordinate on theProcess Flowsheet (Twips)
Ycoordinate = Y coordinate on theProcess Flowsheet (Twips)
Delete(What) Delete a verticalseparator
What = Index as Name (String) orNumber (Integer/Long)
Properties
Name Description Attributes Arguments
Count Number of items inthe collection
Long, read-only
Item(What) Indexed item in thecollection
IVerticalSeparator, read-only
What = Index as Name(String) Or Number(Integer/Long)
Example – Automation InVisual BasicThis example shows how that Aspen Flare System Analyzer can be used as anautomation server by a program that analyses an Aspen Flare SystemAnalyzer model to search for the maximum and minimum values of a userdefined named property within all the pipes.
Note: Although Visual Basic 6 is recommended for this example, you maycreate the Automation application in the Visual Basic editor provided inMicrosoft Excel 2007® (or later) and Microsoft Word 2007® (or later).
1 Open a new project in Visual Basic 6®. From the New tab of the NewProject property view; select the Standard EXE icon and click OK. Yourscreen should appear similar as below.
148
Fig 8.6
2 By default you should have a form associated with thName field of thefrmBounds.
Note: This complete example has also been pre\Samples\Ole\Vb
3 In the Caption field typProperty Boundsform.
4 Before adding objects to the fordifferent objects that will be rProperties wvalue such that the
5 From the Tool Box selectshown below.
By default you should have a form associated with the project. In thefield of the Properties window, give the form the name:
This complete example has also been pre-built and is located in theVb\Bounds directory.
In the Caption field type: Aspen Flare System AnalyzerProperty Bounds. This caption should now appear in the title bar of the
Before adding objects to the form, resize the view to accommodate thedifferent objects that will be required. In the Width filed found in the
window, change the width of the form to 6900value such that the form is sufficiently wide to fully display the caption.
From the Tool Box select Text Box; create a text box on the form as.
8 Automation
e project. In thegive the form the name:
built and is located in the
Model Pipe. This caption should now appear in the title bar of the
, resize the view to accommodate thefiled found in the
00 or to anyis sufficiently wide to fully display the caption.
te a text box on the form as
8 Automation
Fig 8.7
6 Ensure that the text box is the active control. This can be done in one oftwo ways:
Select the text box on the form so that the object guides appear aroundthe object.
From the boxof the text box you have just created.
7 In the Properties windows, set the name of the text box asebModelNamedefault text that appears inside the edit box by entering a new name inthe Text field.
8 You may add a label to the form. i.e. to identify the object from others, byselecting thetext box you have just created.
9 Ensuring that the label control is active using one of the methodssuggested in step 6, go to thein the Caption
Ensure that the text box is the active control. This can be done in one of
Select the text box on the form so that the object guides appear aroundthe object.
box found at the top of the Properties window,of the text box you have just created.
In the Properties windows, set the name of the text box asebModelName in the Name field. If you wish, you may also change thedefault text that appears inside the edit box by entering a new name in
field.
You may add a label to the form. i.e. to identify the object from others, byselecting the Label tool and drawing the label on the form just above thetext box you have just created.
Ensuring that the label control is active using one of the methodssuggested in step 6, go to the Properties Window and change the text
Caption field to Model Name.
149
Ensure that the text box is the active control. This can be done in one of
Select the text box on the form so that the object guides appear around
select the name
In the Properties windows, set the name of the text box aslso change the
default text that appears inside the edit box by entering a new name in
You may add a label to the form. i.e. to identify the object from others, byabel on the form just above the
Ensuring that the label control is active using one of the methodsand change the text
150
Fig 8.8
10 Add the following objects to the form using the previously describedmethods.
Fig 8.9
11 Only two more objects are required on the form. Select theButton control from the tool bar and add two buttons to the form asshown below.
Add the following objects to the form using the previously described
Only two more objects are required on the form. Select thecontrol from the tool bar and add two buttons to the form as
below.
8 Automation
Add the following objects to the form using the previously described
Only two more objects are required on the form. Select the Commandcontrol from the tool bar and add two buttons to the form as
8 Automation
Fig 8.10
12 You are now ready to begin defining the events behind the form andobjects. You may enter the code environment using a number of methods
Click View Code
Select Code from the
Double-click the
You are now ready to begin defining the events behind the form andobjects. You may enter the code environment using a number of methods
View Code in the Project window.
from the View menu.
click the frmBounds form.
151
You are now ready to begin defining the events behind the form andobjects. You may enter the code environment using a number of methods:
152
Fig 8.11
The Private Sub Form_Load()you enter the code environment by double
13 Begin by declaring the following variables under the Option ExplicitDeclaration.
Fig 8.12
14 Add a reference to the Aspen Flare System Analyzer type library to allowaccess to predefined constantmenu.
Private Sub Form_Load() method definition will only be visible ifyou enter the code environment by double-clicking the form.
Begin by declaring the following variables under the Option Explicit
Add a reference to the Aspen Flare System Analyzer type library to allowaccess to predefined constants by selecting References from the
8 Automation
method definition will only be visible ifclicking the form.
Begin by declaring the following variables under the Option Explicit
Add a reference to the Aspen Flare System Analyzer type library to allowfrom the Project
8 Automation
Fig 8.13
15 The first subroutine should already be declared. Thesubroutine is the first subroutine called once the program is run. It isusually used to initializEnter the following code into the
Code
Private SubForm_Load()
ebModelName.Text = ""ebPropertyName.Text =""ebMinValue.Text = ""ebMaxValue.Text = ""
End Sub
16 The next section of code to be added is what will occur when the name ofthe model is changed in the
Code
Private SubebModelName_Validate(CancelAs Boolean)
ModelName = ebModelName.Text
End Sub
The first subroutine should already be declared. The Form_Loadsubroutine is the first subroutine called once the program is run. It isusually used to initialize the variables and objects used by the program.Enter the following code into the Form_Load subroutine.
Explanation
Private SubForm_Load()
Signifies the start of the form load subroutine.You do not have to add as it should already bethere.
elName.Text = ""ebPropertyName.Text =
ebMinValue.Text = ""ebMaxValue.Text = ""
Clears all the text fields.
Signifies the end of the initialization subroutine.This line does not need to be added.
ection of code to be added is what will occur when the name ofthe model is changed in the ebModelName box.
Explanation
Private SubebModelName_Validate(CancelAs Boolean)
Signifies the start of the subroutine.
ModelName = ebModelName.Text Copies the entered name for the modelto the String Variable ModelName
Signifies the end of the subroutine.
153
Form_Loadsubroutine is the first subroutine called once the program is run. It is
e the variables and objects used by the program.
Signifies the start of the form load subroutine.You do not have to add as it should already be
Signifies the end of the initialization subroutine.This line does not need to be added.
ection of code to be added is what will occur when the name of
Signifies the start of the subroutine.
e entered name for the modelto the String Variable ModelName
Signifies the end of the subroutine.
154 8 Automation
17 The next section of code to be added is what will occur when the desiredproperty is changed in the ebPropertyName box.
Code Explanation
Private SubebPropertyName_Validate(Cancel As Boolean)
Signifies the start of the subroutine.
PropertyName =ebPropertyName.Text
Copies the entered name for theproperty to the String VariablePropertyName
End Sub Signifies the end of the subroutine.
18 The final two routines define the actions of the two buttons: btnUpdateand btnExit.
Code Explanation
Private Sub btnUpdate_Click() Signifies the start of the subroutine.
Dim OwnedByMe As BooleanDim MaxVal As DoubleDim MinVal As DoubleDim Pipe AsAspenTech.FlareSystemAnalyzer.InterfacesObjectDim iPipe As LongDim npipes As LongDim WorkVal As Double
Declare work variables.
On Error Resume Next Prevents an error from being raisedif, for example, an invalid name forthe property is selected.
If Trim$(ModelName) = "" ThenOwnedByMe = FalseSet FnApp = GetObject(,
"AspenTech.FlareSystemAnalyzer.Interfaces.Application")Else
Set FnApp =CreateObject("AspenTech.FlareSystemAnalyzer.Interfaces.Application")
OwnedByMe = TrueFnApp.OpenModel ModelName
End If
If a model name is defined thenopens the model defined by theString variable ModelName;otherwise, connects to the currentlyrunning instance of Aspen FlareSystem Analyzer.
If Not FnApp Is Nothing Then Ensure successful connection to theApplication object.
MaxVal = -10000000000#MinVal = 10000000000#
Initializes the maximum andminimum values to values outsidethe range of possible values.
npipes = FnApp.Pipes.CountFor iPipe = 1 To npipes
Set pipe =FnApp.Pipes.Item(iPipe)
Loop through all the pipes in themodel.
8 Automation 155
Code Explanation
WorkVal =Pipe.PropertyByName(PropertyName)
Get the property named and storesin the String variablePropertyName.
If WorkVal <>fntVariableStatus_fntUnknownValue Then
Check for an unknown value. Do notconsider the value further if it isunknown.
If WorkVal > MaxVal Then MaxVal= WorkVal
Update maximum value.
If WorkVal < MinVal Then MinVal= WorkVal
Update minimum value.
End IfNext iPipe
End of loop and value update.
ebMinValue.Text =Format$(MinVal, "0.000e+00")ebMaxValue.Text =Format$(MaxVal, "0.000e+00")
Update the displayed values in theebMinValue and ebMaxValue Textboxes.
Set FnApp = NothingEnd If
Disconnect the Application object.
End Sub Signifies the end of the subroutine.
Private SubbtnExit_Click()
Signifies the start of the subroutine.
Set FnApp = Nothing Releases the connection to Aspen FlareSystem Analyzer.
Unload MeEnd
Unload the form and end the program.
End Sub Signifies the end of the subroutine.
19 You are now ready to compile and run the program. Before you begin,please ensure that you have a copy of Aspen Flare System Analyzer onthe computer.
20 To compile the program do one of the following:
Click the Start button...
Select Start from the Run menu.
Press <F5> from the keyboard.
Visual Basic will inform you of any errors that occur during compile time.
Updating Automation FilesFrom Previous VersionsAspen Flare System Analyzer now uses a new .Net interface to provide accessto the software via automation. As a result a few changes have to be made inthe way the VB6 application code accesses the available methods andproperties. If you have an existing application, it may fail to run with the new
156 8 Automation
interface. Below are some notes on what needs to be updated in yourapplications to ensure it runs successfully in this new version.
1 Currently Application.Visible can only be set to False. The user
cannot make the application visible. The application will be running asusual in the background. The LaunchFlarenet method described in thischapter can be used to launch a separate process showing the graphicaluser interface. This process can only be controlled manually and needs tobe manually terminated as well.
2 In the declarations Integer should be replaced by Long.
3 Objects cannot be enumerated in a collection. Previously you could writethe following code:Dim Pipe As ObjectFor Each Pipe In FnApp.Pipes
WorkVal = Pipe.PropertyByName(PropertyName)…
Next
Now this type of code must be written as follows:Dim iPipe As LongDim npipes As LongFor iPipe = 1 To npipes
Set pipe = FnApp.Pipes.Item(iPipe)WorkVal = pipe.PropertyByName(PropertyName)…
Next iPipe
4 In VB6 enum values are actually constants, thus Enum members can beused directly without the Enum type, e.g. fntUnknownValue. In VB.Net
the Enum type is just a type, not a constant. Also in VB6 it is not possibleto have items of the same name under different Enums, e.g.fntFlowRegime.fntUnknownValue and
fntVariableStatus.fntUnknownValue. Therefore to avoid this issue,
MicroSoft determines that all Enum items should be renamed by havingtheir Enum type as prefix followed by character _. Thus existing codemust be modified to include the new Enum item names. For instance,instead of fntUnknownValue for Variable Status, we now have
fntVariableStatus_fntUnknownValue. Please look in the
AspenTech.FlareSystem.Analyzer Object Browser for the new Enum items’names.
9 Theoretical Basis 157
9 Theoretical Basis
Pressure Drop
Pipe Pressure Drop Method
Vapor Phase Pressure Drop Methods
Pressure drop can be calculated either from the theoretically derived equationfor isothermal flow of a compressible fluid in a horizontal pipe2:
02
2In
221
22
2
1
2
a
GLf
RT
PPM
P
P
a
Gf
9.1
weightMolecularM
eTemperaturT
lengthEquivalentL
diameterInternal
factorfrictionFanningf
constantgasUniversalR
pressureDownstreamP
pressureUpstreamP
pipeofareasectionalCrossa
flowMassG
where
f
2
1
:
158 9 Theoretical Basis
Or from the theoretically derived equation for adiabatic flow of a compressiblefluid in a horizontal pipe2:
1
2
2
2
1
2
1
1 Inγ
1γ1
2γ
1-γ
V
V
V
V
G
a
V
PLAf f
9.2
heatsspecificofRatio
lengthEquivalentL
diameterInternal
factorfrictionFanningf
volumespecificDownstreamV
volumespecificUpstreamV
constantgasUniversalR
pressureUpstreamP
pipeofareasectionalCrossa
flowMassG
where
f
γ
:
2
1
1
The friction factor is calculated using an equation appropriate for the flowregime. These equations correlate the friction factor to the pipe diameter,Reynolds number and roughness of the pipe4:
Turbulent Flow (Re > 4000)
The friction factor may be calculated from either the Round equation:
5.6135.0log61.3
1e
fRe
Re
f
9.3
roughnesspipeAbsolutee
diameterInternal
numberReynoldsRe
factorfrictionFanningf
where
f
:
Or from the Chen21 equation:
8981.01098.1149.7
8257.2
/log
0452.5
7065.3
/log4
1
Re
e
Re
e
f f
9 Theoretical Basis 159
9.4
roughnesspipeAbsolutee
diameterInternal
numberReynoldsRe
factorfrictionFanningf
where
f
:
Transition Flow (2100 Re 4000)
Re
e
Re
e
Re
e
f f
0.13
7.3log
02.5
7.3log
02.5
7.3log0.4
1
9.5
roughnesspipeAbsolutee
diameterInternal
numberReynoldsRe
factorfrictionFanningf
where
f
:
Laminar Flow (Re < 2100)
Ref f
16
9.6
numberReynoldsRe
factorfrictionFanningf
where
f
:
The Moody friction factor is related to the Fanning friction factor by:
fm ff 4
9.7
factorfrictionMoodyf
factorfrictionFanningf
where
m
f
:
160 9 Theoretical Basis
2-Phase Pressure Drop
Although the Beggs and Brill method was not intended for use with verticalpipes, it is nevertheless commonly used for this purpose, and is thereforeincluded as an option for vertical pressure drop methods.
Beggs and Brill
The Beggs and Brill9 method is based on work done with an air-water mixtureat many different conditions, and is applicable for inclined flow. In the Beggsand Brill correlation, the flow regime is determined using the Froude numberand inlet liquid content. The flow map used is based on horizontal flow andhas four regimes: segregated, intermittent, distributed and transition. Oncethe flow regime has been determined, the liquid hold-up for a horizontal pipeis calculated, using the correlation applicable to that regime. A factor isapplied to this hold-up to account for pipe inclination. From the hold-up, atwo-phase friction factor is calculated and the pressure gradient determined.
Fig 9.1
The boundaries between regions are defined in terms of two constants andthe Froude number10:
321 0207.0481.0757.362.4exp xxxL
9.8
5322 000625.00179.0609.1602.4061.1exp xxxxL
9 Theoretical Basis 161
9.9
flowratevolumetricsituInq
qqqcontentliquidInput
Inx
where
gasliquidliquid
/λ
λ
:
According to Beggs and Brill:
1 If the Froude number is less than L1, the flow pattern is segregated.
2 If the Froude number is greater than both L1 and L2, the flow pattern isdistributed.
3 If the Froude number is greater than L1 and smaller than L2 the flowpattern is intermittent.
Dukler Method
The Dukler10 method breaks the pressure drop into three components -Friction, Elevation and Acceleration. The total pressure drop is the sum of thepressure drop due to these components:
AEFTotal PPPP
9.10
onacceleratitoduepressureinChangeP
elevationtoduepressureinChangeP
frictiontoduepressureinChangeP
pressureinchangeTotalP
where
A
E
F
Total
:
The pressure drop due to friction is:
Dg
VLfP
c
mmTPF
144
ρ22
9.11
)(
)/2.32(g
)/(ρ
)/(
)(
)(
:
2
3
ftpipeofdiameterInsideD
slbfftlbmconstantnalGravitatio
ftlbmixturephasetwoofDensity
sftvelocity
equalassumingpipelineinmixturephasetwotheofVelocityV
ftpipelinetheoflengthEquivalentL
yempiricalldeterminedfactorfrictionphaseTwof
where
c
m
m
TP
162 9 Theoretical Basis
The pressure drop due to elevation is as follows:
144
ρ
HEP
Lh
E
9.12
changeselevationofSumH
densityLiquid
yempiricalldeterminedfactorheadLiquidE
where
L
h
ρ
)(
:
The pressure drop due to acceleration is usually very small in oil/gasdistribution systems, but becomes significant in flare systems:
θcos
ρ
1
ρρ
1
ρ
144
1 2222
2
USL
LPLL
L
GPLg
DSL
LPLL
L
GPLg
c
AR
Q
R
Q
R
Q
R
Q
AgP
9.13
bendpipetheofAngle
capacitypipelineofpercentageaaspipelineinholdupLiquidR
hrftpressureandetemperaturpipelineatflowingliquidofVolumeQ
hrftpressureandetemperaturpipelineatflowinggasofVolumeQ
densityGas
areasectionalCrossA
where
L
LPL
GPL
g
θ
)/(
)/(
ρ
:
3
3
Orkiszewski Method
The Orkiszewski11,12 method assumes there are four different flow regimesexisting in vertical two-phase flow - bubble, slug, annular-slug transition andannular-mist.
The bubble flow regime consists mainly of liquid with a small amount of afree-gas phase. The gas phase consists of small, randomly distributed gasbubbles with varying diameters. The gas phase has little effect on thepressure gradient (with the exception of its density).
In the slug flow regime, the gas phase is most pronounced. The gas bubblescoalesce and form stable bubbles of approximately the same size and shape.The gas bubbles are separated by slugs of a continuous liquid phase. There isa film of liquid around the gas bubbles. The gas bubbles move faster than theliquid phase. At high flow velocities, the liquid can become entrained in thegas bubbles. The gas and liquid phases may have significant effects on thepressure gradient.
Transition flow is the regime where the change from a continuous liquid phaseto a continuous gas phase occurs. In this regime, the gas phase becomes
9 Theoretical Basis 163
more dominant, with a significant amount of liquid becoming entrained in thegas phase. The liquid slug between the gas bubbles virtually disappears in thetransition regime.
In the annular-mist regime, the gas phase is continuous and is the controllingphase. The bulk of the liquid is entrained and carried in the gas phase.
Orkiszewski defined bubble flow, slug flow, mist flow and gas velocitynumbers which are used to determine the appropriate flow regime.
If the ratio of superficial gas velocity to the non-slip velocity is less than thebubble flow number, then bubble flow exists, for which the pressure drop is:
Dg
R
V
fPc
L
sL
Ltp2
ρ
2
9.14
)(
)/2.32(
)/(
)/(ρ
)/(
:
2
3
2
ftdiameterHydraulicD
slbfftlbmconstantnalGravitatiog
velocityslipnonondependentfactoressDimensionlR
sftvelocityliquidlSuperficiaV
ftlbdensityLiquid
factorfrictionphaseTwof
lengthoffootperftlbdropPressureP
where
c
L
sL
L
tp
If the ratio of superficial gas velocity to the non-slip velocity is greater thanthe bubble flow number, and the gas velocity number is smaller than the slugflow number, then slug flow exists. The pressure drop in this case is:
rns
rsL
c
nsLtp
VV
VV
Dg
VfP
2
ρ 2
9.15
Constant
velocityriseBubbleV
velocityslipNonV
where
r
ns
:
The pressure drop calculation for mist flow is as follows:
Dg
VfP
c
sg
gtp2
ρ
2
164 9 Theoretical Basis
9.16
)/(ρ
)/(
:
3ftlbdensityGas
sftvelocitygaslSuperficiaV
where
g
sg
The pressure drop for transition flow is:
ms PxPP 1
9.17
numbersvelocitygasandflowslugflowmistondependentfactorWeightingx
flowmixedfordropPressurePm
flowslugfordropPressurePs
where
,,,
:
The pressure drop calculated by the previous equations, are for a one-footlength of pipe. These are converted to total pressure drop by:
246371144
ρ
p
ftotal
total
PA
GQ
PLP
9.18
)(
)(
)(
)(
)/(
)/(/
)/(ρ
:
2
3
3
ftsegmentlineofLengthL
abovecalculatedasdroppressureUnitP
psiasegmentinpressureAveragep
ftpipeofareasectionalCrossA
sftrateflowGasG
slbgasliquidcombinedofrateMassQ
ftlbregimeflowingtheofDensity
where
p
f
total
9 Theoretical Basis 165
Fittings Pressure Change MethodsThe correlations used for the calculation of the pressure change across afitting are expressed using either the change in static pressure or the changein total pressure. Static pressure and total pressure are related by therelationship:
2
ρ 2vPP st
9.19
In this equation and all subsequent equations, the subscript t refers to totalpressure and the subscript s refers to the static pressure.
Enlargers/Contractions
The pressure change across an enlargement or contraction may be calculatedusing either incompressible or compressible methods. For two phase systemsa correction factor that takes into account the effect of slip between thephases may be applied.
Figure A.2 and A.3 define the configurations for enlargements andcontractions. In these figures the subscript 1 always refers to the fitting inletand subscript 2 always refers to the fitting outlet.
Fig 9.2
Fig 9.3
166 9 Theoretical Basis
Fitting Friction Loss Coefficient
The friction loss coefficients for Enlargements & Contractions are given by:
Sudden and Gradual Enlargement
For an enlarger, both Crane & HTFS methods use the same the fittings losscoefficients which are defined by Crane26. These methods are based on theratio of smaller diameter to larger diameter (β).
If < 45
221 β1
2
θsin6.2
K
9.20
Otherwise
221 β1K
9.21
2
1β
diameterlarger odiameter tsmaller of ratio theis β where,
d
d
Sudden and Gradual Contraction
For a contraction the fittings loss coefficient in Crane & HTFS methods arecalculated differently for abrupt sudden contractions. Otherwise thecoefficients are same for Crane & HTFS methods. These calculation methodsare as described below:
Crane
The fitting loss coefficient is calculated as per HTFS27. These methods are
based on the ratio of smaller diameter to larger diameter (β).
21σ
ctCKK
9.22
57806.00.39543σ
σ5385.4σ24265.14σ54038.8σ2211.190.5
1.52.52
tK
9.23
2
1
2σ
d
d
where:
9 Theoretical Basis 167
The contraction coefficient, is defined by
25.079028.4θ'6240.9 θ'1θ'03614.00179.0 leCc
9.24
oθ/180θ'
:
where
HTFS
The fittings loss coefficients are defined by HTFS27. These methods are same
as the previous Crane method (Equations A.22 – A.24) except for suddencontractions where the contraction coefficient is calculated differently.
If θ = 180 (Abrupt contraction)
σ-10.411
1
cC
9.25
Incompressible Single Phase Flow
The total pressure change across the fitting is given by:
2
ρ 211
1
vKPt
9.26
Velocityv
densityMass
tcoefficienlossFittingsK
changepressureTotalp
where
ρ
:
1
Incompressible Two Phase Flow
Sudden and Gradual Enlargement
The static pressure change across the fitting is given by HTFS27
2
2121
2ρ
σ
11
LO
l
s
mK
P
9.27
g
g
g
l
g
gLO
xx
ε-1
1
ρ
ρ
ε
222
168 9 Theoretical Basis
9.28
tcoefficienlossFittingsK
fractionmassPhasex
fractionvoidPhase
densitymassPhase
fluxMassm
where
1
ε
ρ
:
Sudden and Gradual Contraction
The static pressure change across the fitting is given by HTFS27
222
2
2ρ
σ1LO
l
ts
mKP
9.29
222 1 gLLO x
9.30
2
2 11
XX
CL
9.31
5.0
ρ
ρ1
l
g
g
g
x
xX
9.32
5.05.0
ρ
ρ
ρ
ρ
l
g
g
lC
9.33
tcoefficienlossFittingsK
fractionmassPhasex
fractionvoidPhase
densitymassPhase
fluxMassm
where
1
ε
ρ
:
9 Theoretical Basis 169
Compressible Single Phase Flow
Sudden and Gradual Enlargement
The static pressure change across the fitting is given by HTFS27
1
σρ
ρ
σρ 2
1
1
21m
Ps
9.34
densitymassPhase
fluxMassm
where
ρ
:
Sudden and Gradual Contraction
The static pressure change across the fitting is calculated using the two-phasemethod given in Compressible Two Phase Flow below. The single-phaseproperties are used in place of the two-phase properties.
Compressible Two Phase Flow
Sudden and Gradual Enlargement
The static pressure change across the fitting is given by HTFS27
1
221
σσE
Es v
vmP
9.35
bygivenvolumespecificEquivalentv
where
E
:
1
11
11
5.0
2
l
g
R
R
g
glgRggE
v
v
u
u
xxvxuvxv
9.36
5.0
l
HR
v
vu
9.37
lgggH vxvxv 1
170 9 Theoretical Basis
9.38
fractionmassPhasex
densitymassPhase
fluxMassm
where
ρ
:
Sudden and Gradual Contraction
The pressure loss comprises two components. These are the contraction ofthe fluid as is passed from the inlet to the vena contracta plus the expansionof the fluid as it passes from the vena contracta to the outlet. In the followingequations the subscript t refers to the condition at the vena contracta.
For the flow from the inlet to the vena conracta, the pressure change ismodeled in accordance with HTFS27 by:
2
2
11
121
ζ
11 σ
11
2ζ
cE
EtE
E
E
Cv
v
P
vmd
v
v
9.39
1
ζP
P
9.40
For the flow from the vena contracta to the outlet the pressure change ismodeled used the methods for Sudden and Gradual Expansion given above.
Tees
Tees can be modeled either by using a flow independent loss coefficient foreach flow path or by using variable loss coefficients that are a function of thevolumetric flow and area for each flow path as well as the branch angle. Thefollowing numbering scheme is used to reference the flow paths.
Fig 9.4
Constant Loss Coefficients
The following static pressure loss coefficients values are suggested by theAPI23:
9 Theoretical Basis 171
θ13K 23K 12K
31K 32K 21K
<90o 0.76 0.50 1.37 0.76 0.50 1.37
90o 1.37 0.38 1.37 1.37 0.38 1.37
The selection of the coefficient value is dependent on the angle and thedirection of flow through the tee.
For flow into the run, the loss coefficient for tee is:
θ13K 12K
90o 0.38 1.37
<>90o 0.50 1.37
For flow into the branch, the loss coefficient for tee is:
θ 21K23K
90o 1.37 1.37
<>90o 1.37 0.76
For flow into the tail, the loss coefficient for tee is:
θ31K 23K
90o 0.38 1.37
<>90o 0.50 0.76
4.32,1: AFigureinshownasassignedareandnumbersReferencewhere
The static pressure change across the fitting is given by:
2
ρ 2vKPs
9.41
Variable Loss Coefficients
The loss coefficients are a function of the branch angle, branch area to totalflow area ratio and branch volumetric flow to total volumetric flow ratio.These coefficients can be determined either from graphical representation byMiller25 or from the Gardel28 equations. Using these methods, static pressurechanges can be calculated from:
Combining Flow
2
ρ
2
ρ
2
ρ
223
3
233
1
211
13v
Pv
Pv
K
172 9 Theoretical Basis
9.42
2
ρ
2
ρ
2
ρ
223
3
233
2
222
23 v
Pv
Pv
K
9.43
Dividing Flow
2
ρ
2
ρ
2
ρ
223
1
211
3
233
31 v
Pv
Pv
K
9.44
2
ρ
2
ρ
2
ρ
223
2
222
3
233
32v
Pv
Pv
K
9.45
Miller Method
A typical Miller chart for 23K in combining flow is shown.
Fig 9.5
Gardel Method
9 Theoretical Basis 173
These coefficients can also be calculated analytically from the Gardel28
Equations given below:
Combining flow:
rr
rr
qqK
12
cos1
118.01
cos2.1192.0
2
2
2
13
rr
rr
qqK
12
138.01cos
62.11103.022
23
9.46
Dividing Flow
rr
rr
qqK
12
tan1
14.0
9.011.04.0
3.02
tan3.1195.02
2
2
31
rrrr qqqqK 12.035.0103.022
32
9.47
Where,
qr = Ratio of volumetric flow rate in branch to total volumetric flow rate
Φ = Area ratio of pipe connected with the branch to the pipe carrying the total flow
ρ = Ratio of the fillet radius of the branch to the radius of the pipe connected with the branch
θ = Angle between branch and main flow as shown in Fig 9.4
Orifice Plates
Orifice plates can be modeled either as a sudden contraction from the inletpipe size to the orifice diameter followed by a sudden expansion from theorifice diameter to the outlet pipe size or by using the HTFS equation for athin orifice plate.
1
21β5082.12
4 ρ2β1
β
2.825 0.08956 mPs
9.48
See Incompressible Single Phase Flow on Page 263 for a definition of thesymbols.
174 9 Theoretical Basis
Vertical Separators
The Pressure change across the separator comprises the followingcomponents:
Expansion of the multiphase inlet from the inlet diameter, d1, to the bodydiameter dbody.
Contraction of vapor phase outlet from the body diameter, dbody, to the outletdiameter, d2
Friction losses are ignored.
Fig 9.6
Horizontal Separators
The Pressure change across the separator comprises the followingcomponents calculated using the methods described in Incompressible SinglePhase Flow on Page 263:
Expansion of the multiphase inlet from the inlet diameter, d1, to the vaporspace characterized by equivalent diameter of the vapor area.
Contraction of vapor phase outlet from the vapor space characterized by theequivalent diameter of the vapor area, to the outlet diameter, d2
Friction losses are ignored.
Fig 9.7
9 Theoretical Basis 175
Vapor-Liquid Equilibrium
Compressible GasThe PVT relationship is expressed as:
ZRTPV
9.49
eTemperaturT
constantGasR
factorilityCompressibZ
VolumeV
PressureP
where
:
The compressibility factor Z is a function of reduced temperature andpressure. The overall critical temperature and pressure are determined usingapplicable mixing rules.
Vapor PressureThe following equations are used for estimating the vapor pressure, given thecomponent critical properties3:
1*0** InωInIn rrr ppp
9.50
60* 169347.0In28862.109648.6
92714.5In rr
r
r TTT
p
176 9 Theoretical Basis
9.51
61* 43577.0In4721.136875.16
2518.15In rr
r
r TTT
p
9.52
)(
)(
)/(
ω
)(
)(
)/(
:
*
**
RetemperaturCriticalT
ReTemperaturT
TTetemperaturReducedT
factorAcentric
abspsipressureCriticalp
abspsipressureVapourp
pppressurevapourReducedp
where
oc
o
cr
c
cr
This equation is restricted to reduced temperatures greater than 0.30, andshould not be used below the freezing point. Its use was intended forhydrocarbons, but it generally works well with water.
Soave Redlich KwongIt was noted by Wilson (1965, 1966) that the main drawback of the Redlich-Kwong equation of state was its inability of accurately reproducing the vaporpressures of pure component constituents of a given mixture. He proposed amodification to the RK equation of state using the acentricity as a correlatingparameter, but this approach was widely ignored until 1972, when Soave(1972) proposed a modification of the SRK equation of this form:
bVV
TTa
bV
RTP c
ω,,
9.53
The a term was fitted in such a way as to reproduce the vapor pressure ofhydrocarbons using the acentric factor as a correlating parameter. This led tothe following development:
bVV
a
bV
RTP c
α
9.54
RK22
assametheP
TRa a
c
cac
9 Theoretical Basis 177
9.55
5.011α rTS
9.56
20.176ω-ω574.1480.0 S
9.57
The reduced form is:
2599.0
3.8473α
2559.0
3
rrr
rr
VVV
TP
9.58
The SRK equation of state can represent with good accuracy the behavior ofhydrocarbon systems for separation operations, and since it is readilyconverted into computer code, its usage has been extensive in the last twentyyears. Other derived thermodynamic properties, like enthalpies and entropies,are reasonably accurate for engineering work, and the SRK equation enjoyswide acceptance in the engineering community today.
Peng RobinsonPeng and Robinson (1976) noted that although the SRK was an improvementover the RK equation for VLE calculations, the densities for the liquid phasewere still in considerable disagreement with experimental values due to auniversal critical compressibility factor of 0.3333, which was still too high.They proposed a modification to the RK equation which reduced the criticalcompressibility to about 0.307, and which would also represent the VLE ofnatural gas systems accurately. This improved equation is represented by:
bVbbVV
a
bV
RTP c
α
9.59
c
cc
P
TRa
22
45724.0
9.60
c
c
P
RTb 07780.0
9.61
They used the same functional dependency for the term as Soave:
178 9 Theoretical Basis
5.011α rTS
9.62
20.26992ω-ω5422.137464.0 S
9.63
0642.05068.0
4.8514α
2534.0
2573.32
rrr
rr
VVV
TP
9.64
The accuracy of the SRK and PR equations of state are roughly the same(except for density calculations).
Physical Properties
Vapor DensityVapor density is calculated using the compressibility factor calculated fromthe Berthalot equation5. This equation correlates the compressibility factor tothe pseudo reduced pressure and pseudo reduced temperature.
2
0.60.10703.00.1
rr
r
TT
PZ
9.65
ZRT
PMρ
9.66
Liquid DensitySaturated liquid volumes are obtained using a corresponding states equationdeveloped by R. W. Hankinson and G. H. Thompson14 which explicitly relatesthe liquid volume of a pure component to its reduced temperature and asecond parameter termed the characteristic volume. This method has beenadopted as an API standard. The pure compound parameters needed in thecorresponding states liquid density (COSTALD) calculations are taken fromthe original tables published by Hankinson and Thompson, and the API databook for components contained in Aspen Flare System Analyzer's library. Theparameters for hypothetical components are based on the API gravity and thegeneralized Lu equation. Although the COSTALD method was developed forsaturated liquid densities, it can be applied to sub-cooled liquid densities, i.e.,
9 Theoretical Basis 179
at pressures greater than the vapor pressure, using the Chueh and Prausnitzcorrection factor for compressed fluids. The COSTALD model was modified toimprove its accuracy to predict the density for all systems whose pseudo-reduced temperature is below 1.0. Above this temperature, the equation ofstate compressibility factor is used to calculate the liquid density.
Vapor ViscosityVapor viscosity is calculated from the Golubev3 method. These equationscorrelate the vapor viscosity to molecular weight, temperature and thepseudo critical properties.
Tr > 1.0
167.0
)/29.071.0(667.05.0
0.10000
5.3μ
c
Trc
T
TPM r
9.67
Tr ≤ 1.0
167.0
)965.0(667.05.0
0.10000
5.3μ
c
rc
T
TPM
9.68
Liquid ViscosityAspen Flare System Analyzer will automatically select the model best suitedfor predicting the phase viscosities of the system under study. The modelselected will be from one of the three available in Aspen Flare SystemAnalyzer: a modification of the NBS method (Ely and Hanley), Twu's model,and a modification of the Letsou-Stiel correlation. Aspen Flare SystemAnalyzer will select the appropriate model using the following criteria:
Chemical System Liquid Phase Methodology
Lt Hydrocarbons (NBP < 155 F) Mod Ely & Hanley
Hvy Hydrocarbons (NBP > 155 F) Twu
Non-Ideal Chemicals Mod Letsou-Stiel
All the models are based on corresponding states principles and have beenmodified for more reliable application. These models were selected since theywere found from internal validation to yield the most reliable results for thechemical systems shown. Viscosity predictions for light hydrocarbon liquidphases and vapor phases were found to be handled more reliably by an in-house modification of the original Ely and Hanley model, heavier hydrocarbonliquids were more effectively handled by Twu's model, and chemical systemswere more accurately handled by an in-house modification of the originalLetsou-Stiel model.
180 9 Theoretical Basis
A complete description of the original corresponding states (NBS) model usedfor viscosity predictions is presented by Ely and Hanley in their NBSpublication16. The original model has been modified to eliminate the iterativeprocedure for calculating the system shape factors. The generalized Leech-Leland shape factor models have been replaced by component specificmodels. Aspen Flare System Analyzer constructs a PVT map for eachcomponent and regresses the shape factor constants such that the PVT mapcan be reproduced using the reference fluid.
Note: The PVT map is constructed using the COSTALD for the liquid region.The shape factor constants for all the library components have already beenregressed and are stored with the pure component properties.
Pseudo component shape factor constants are regressed when the physicalproperties are supplied. Kinematic or dynamic viscosity versus temperaturecurves may be supplied to replace Aspen Flare System Analyzer's internalpure component viscosity correlations. Aspen Flare System Analyzer uses theviscosity curves, whether supplied or internally calculated, with the physicalproperties to generate a PVT map and regress the shape factor constants.Pure component data is not required, but if it is available it will increase theaccuracy of the calculation.
The general model employs methane as a reference fluid and is applicable tothe entire range of non-polar fluid mixtures in the hydrocarbon industry.Accuracy for highly aromatic or naphthenic oil will be increased by supplyingviscosity curves when available, since the pure component propertygenerators were developed for average crude oils. The model also handleswater and acid gases as well as quantum gases.
Although the modified NBS model handles these systems very well, the Twumethod was found to do a better job of predicting the viscosities of heavierhydrocarbon liquids. The Twu model18 is also based on corresponding statesprinciples, but has implemented a viscosity correlation for n-alkanes as itsreference fluid instead of methane. A complete description of this model isgiven in the paper18 titled "Internally Consistent Correlation for PredictingLiquid Viscosities of Petroleum Fractions".
For chemical systems the modified NBS model of Ely and Hanley is used forpredicting vapor phase viscosities, whereas a modified form of the Letsou-Stiel model15 is used for predicting the liquid viscosities. This method is alsobased on corresponding states principles and was found to performsatisfactorily for the components tested.
The parameters supplied for all Aspen Flare System Analyzer pure librarycomponents have been fit to match existing viscosity data over a broadoperating range. Although this will yield good viscosity predictions as anaverage over the entire range, improved accuracy over a more narrowoperating range can be achieved by supplying viscosity curves for any givencomponent. This may be achieved either by modifying an existing librarycomponent through Aspen Flare System Analyzer's component librarian or byentering the desired component as a hypothetical and supplying its viscositycurve.
9 Theoretical Basis 181
Liquid Phase Mixing Rules for ViscosityThe estimates of the apparent liquid phase viscosity of immiscibleHydrocarbon Liquid - Aqueous mixtures are calculated using the following"mixing rules":
If the volume fraction of the hydrocarbon phase is greater than or equal to0.33, the following equation is used19:
oilvoileff e 16.3μμ
9.69
phasenHydrocarbofractionVolumev
phasenHydrocarboofViscosity
viscosityApparent
where
oil
oil
eff
μ
μ
:
If the volume fraction of the hydrocarbon phase is less than 0.33, thefollowing equation is used20:
OH
OHoil
OHoil
oileff v2
2
2 μμμ
μ4.0μ5.21μ
9.70
phasenHydrocarbofractionVolumev
phaseAqueousofViscosity
phasenHydrocarboofViscosity
viscosityApparent
where
oil
OH
oil
eff
2μ
μ
μ
:
The remaining properties of the pseudo phase are calculated as follows:
)( weightmolecularmwxmw iieff
9.71
)(//1ρ densitymixturepx iieff
9.72
)( heatspecificmistureCpxCp iieff
182 9 Theoretical Basis
9.73
Thermal ConductivityAs in viscosity predictions, a number of different models and componentspecific correlations are implemented for prediction of liquid and vapor phasethermal conductivities. The text by Reid, Prausnitz and Polings15 was used asa general guideline in determining which model was best suited for each classof components. For hydrocarbon systems the corresponding states methodproposed by Ely and Hanley16 is generally used. The method requiresmolecular weight, acentric factor and ideal heat capacity for each component.These parameters are tabulated for all library components and may either beinput or calculated for hypothetical components. It is recommended that all ofthese parameters be supplied for non-hydrocarbon hypotheticals to ensurereliable thermal conductivity coefficients and enthalpy departures.
The modifications to the method are identical to those for the viscositycalculations. Shape factors calculated in the viscosity routines are useddirectly in the thermal conductivity equations. The accuracy of the methodwill depend on the consistency of the original PVT map.
The Sato-Reidel method15 is used for liquid phase thermal conductivitypredictions of glycols and acids, the Latini et al. Method15 is used for esters,alcohols and light hydrocarbons in the range of C3 - C7, and the Missenardand Reidel method15 is used for the remaining components.
For vapor phase thermal conductivity predictions, the Misic and Thodos, andChung et al. 15 methods are used. The effect of higher pressure on thermalconductivities is taken into account by the Chung et al. method.
As in viscosity, the thermal conductivity for two liquid phases is approximatedby using empirical mixing rules for generating a single pseudo liquid phaseproperty.
Enthalpy
Ideal Gas
The ideal gas enthalpy is calculated from the following equation:
432 TETDTCTBAH iiiiiideal
9.74
termscapacityheatgasIdealEDCBA
eTemperaturT
enthalpyIdealH
where
,,,,
:
9 Theoretical Basis 183
Lee-Kesler
The Lee-Kesler enthalpy method corrects the ideal gas enthalpy fortemperature and pressure.
depideal HHH
9.75
s
c
depr
c
dep
r
s
c
dep
c
dep
RT
H
RT
H
RT
H
RT
H
ω
ω
9.76
E
VT
d
VT
T
cc
VT
T
b
T
bb
ZTRT
H
rr
k
rr
r
kk
rr
t
k
r
kk
kr
k
c
dep
352
332
0.15
22
23
2243
2
9.77
2
γ
234 γ
1β0.1βγ2
r
k
V
r
kkk
kr
k
eVT
cE
9.78
enthalpydeparturegasIdealH
termsKeslerLeedcb
enthalpyIdealH
fluidSimples
fluidReferencer
factorAcentric
enthalpySpecificH
etemperaturCriticalT
where
dep
ideal
c
γβ,,,,
ω
:
Equations of State
The Enthalpy and Entropy calculations are performed rigorously using thefollowing exact thermodynamic relations:
dVPT
PT
RTZ
RT
HHV
V
ID
11
184 9 Theoretical Basis
9.79
dVVT
P
RP
PZ
R
SSV
Vo
IDo
11InIn
9.80
For the Peng Robinson Equation of State, we have:
bV
bV
dt
daTa
bRTZ
RT
HH ID
12
12In
2
11
5.0
5.0
5.1
9.81
BZ
BZ
adT
Tda
B
A
P
PBZ
R
SSo
IDo
12
12In
2InIn
5.0
5.0
5.1
9.82
ijji
N
i
N
jji kaaxxa
where
1
:
5.0
1 1
9.83
For the SRK Equation of State:
V
b
dt
daTa
bRTZ
RT
HH ID
1In1
1
9.84
Z
B
adT
Tda
B
A
P
PBZ
R
SSo
IDo 1InInIn
9.85
A and B term definitions are provided below:
Term Peng-Robinson Soave-Redlich-Kwong
ib
ci
ci
P
RT077796.0
ci
ci
P
RT08664.0
ia icia α icia α
9 Theoretical Basis 185
Term Peng-Robinson Soave-Redlich-Kwong
cia
ci
ci
P
RT2
457235.0
ci
ci
P
RT2
42748.0
iα 5.011 rii Tm 5.011 rii Tm
im 2ω26992.0ω54226.137646.0 ii 2ω176.0ω57.148.0 ii
ijji
N
i
N
jji kaaxxa
where
1
:
5.0
1 1
9.86
N
iiibxb
and
1
9.87
EntropyS
EnthalpyH
constantgasIdealR
stateReference
gasIdealIDo
186 9 Theoretical Basis
NoiseThe sound pressure level at a given distance from the pipe is calculated fromthe following equations. In these equations the noise producing mechanism isassumed to be solely due to the pressure drop due to friction.
4
π36.1
2
L
PWm v
9.88
tr
LWSPL m
r
2
13
π4
η10log10
9.89
velocityfluidAveragev
lossontransmissiwallPipet
pressureinChangeP
efficiencyAcoustic
diameterInternal
pipefromDistancer
levelpressureSoundSPL
lengthEquivalentL
where
η
:
9 Theoretical Basis 187
Fig 9.8
The transmission loss due to the pipe wall is calculated from:
0.365.0
0.17
mvt
9.90
velocityfluidAveragev
diameterInternal
areaunitpermasswallPipem
where
:
The acoustical efficiency is calculated from the equation below.
5388.9ln*9986.4exp MPr
9.91
where
Pr = Ratio of higher absolute Pr over lower absolute Pr between two ends ofthe pipe (i.e. if upstream pr.> downstream pr., Pr = upstreampr./downstream pr. Else if upstream pr.< downstream pr., Pr = downstreampr./upstream pr.)
M = Mach No.
0 .0 0.2 0 .4 0 .6 0.8 1.0
Mach N um ber
10 - 11
10 - 10
10 - 9
10 - 8
10 - 7
10 - 6
1 0-5
10 - 4
10 - 3
Aco
usti
cal
Eff
icie
nc
y
pt = 1 0.0
p t = 1.0
p t = 0.1
188 9 Theoretical Basis
A File Format 189
A File Format
Import/Export DetailsThis section provides further details of the import and export capabilities ofAspen Flare System Analyzer.
Important! The definition format for Import/Export has changed since AspenFlare System Analyzer V7.3. As a result, if you are using Aspen Flare SystemAnalyzer V7.3 or later, you cannot import files generated from Aspen FlareSystem Analyzer V7.2 and earlier versions or export on top of a file that hasbeen generated using Aspen Flare System Analyzer V7.2 or earlier versions.
Process Descriptions
Import Wizard
The purpose of this section of the documentation is to describe step by stepthe operation of the import wizard.
End of Step 1
At this stage the import process verifies that the specified import file existsand opens it. The import wizard is then configured for the appropriate filetype.
Any errors are reported.
End of Step 2
At this stage the import process opens the specified import definition file orthe default or new import definition file as specified in Preferences asappropriate. A check is made that the import definition file type matches thefile type specified in step 1. The version of the import definition file is thenchecked; data object and data item elements are added to update to thecurrent Aspen Flare System Analyzer version if required.
The next step is to process the file to build the object selector tree view forStep 3. Any problems in reading the import definition file are reported.
190 A File Format
Step 3
During this step, the Import Wizard extracts Source tab data and FieldDetails for each data item as different data objects are selected. Whenever anew data object is selected, the data on the Source tab is validated and anyproblems are reported.
End of Step 4
The first action taken is to save the import definition file if required,prompting for the file name to be used. The import process then begins. Indetail, the steps are:
1 Clear current results.
2 Open log file if required.
3 Read components one by one. For each component check to see if italready exists in the current Aspen Flare System Analyzer case. If not,add the component to list. For database components, use informationfrom database; otherwise, use the data values from file.
4 Read binary interaction parameter data.
5 Read data for pipes, connector nodes and source nodes one object type ata time; updating the progress view as appropriate.
6 As each instance of a particular object type is read, check if it alreadyexists. If so, use the data read to update it; otherwise, create a newinstance of the appropriate object type.
7 Make connections between pipes and nodes. Processing allows for onlyone end of the connection to be read.
8 Read scenario data. Existing scenarios will be updated, and new onescreated if required.
9 Read Solver options.
10 Update automatic calculations to reflect new data values.
11 Refresh all views.
12 Close log file, and then close Import Data File. Any background copy ofExcel will be closed at this point.
13 Close the Import Wizard and finish.
General Data Object Import Procedure
For each object type that is read, the detailed import procedure is as follows:
1 Check to see if import of this object type is required. Quit reading thistype of data object if not.
2 Process the data object definition data from the Import Definition File.Search for and open the specified source object. Quit if any errors areencountered.
3 Search the source data object for an instance of the appropriate objecttype using the defined select criteria if required. For Access imports, thiswill be a row in the specified table; for Excel imports, this will be a row orcolumn range in the specified worksheet where cell offset 1,1 is not blank;for XML imports, this will be an item element within the specified groupelement.
4 Repeat steps 2 and 3 to open any sub section data objects.
A File Format 191
5 Read data items from source one by one.
6 Update counters for number of instances read and search data source fornext object instance. For an Access imports, this will be the next row; forExcel imports, the next row or column range; for XML imports, the nextitem element. Selection criteria will apply if specified. Quit if the nextinstance cannot be found.
7 Repeat steps 5 and 6 until all instances have been read.
Export Process
The purpose of this section of the documentation is to describe step by stepthe operation of the export wizard.
End of Step 1
At this stage the export process checks to see if the target export file exists.If so, it opens the file; otherwise, a new file with the defined name is created.The Export Wizard is then configured for the appropriate file type.
Any errors are reported.
End of Step 2
At this stage, the export process opens the specified export definition file orthe default or new export definition file specified in Preferences asappropriate. A check is made that the export definition file type matches thefile type specified in step 1. The version of the export definition file is thenchecked and data object and data item elements are added to update it to thecurrent Aspen Flare System Analyzer version if required.
The next step is to process the file to build the object selector tree view forStep 3. Any problems in reading the export definition file are reported.
Step 3
During this step, the Export Wizard extracts Target tab data and FieldDetails for each data item as different data objects are selected. Whenever anew data object is selected, the data on the Target tab is validated and anyproblems are reported.
End of Step 4
The first action taken is to save the export definition file if required,prompting for the file name to be used. The export process then begins. Indetail the steps are:
1 Clear existing data from export file if requested.
2 Write components data.
3 Write binary interaction parameter data.
4 Write pipe data.
5 Write connector node and source node data, working through each type ofnode in turn.
6 Write scenario data for scenarios that are selected for calculation.
192 A File Format
7 Write results data for scenarios that are selected for calculation.
8 Write solver options.
9 Save export file. Any background copy of Excel will be closed at this point.
10 Close the Export Wizard.
General Data Object Export Procedure
For each object type that is written, the detailed export procedure is asfollows:
1 Check that export of this data object type is required. Quit if not.
2 Create target data object using information from export definition file. ForAccess export, this will create a table with the correct fields; for Excelexport, a worksheet with the correct name; for XML export, a group tagwith the correct name. Quit if any errors are encountered.
3 Create target data objects as required for any data subsections.
4 For each instance of the data object to be written, search the output file tosee if this instance already exists. If so, select this to be overwritten;otherwise, create a new instance for the data object in the output file. ForAccess export, this will be a new row in that target table; for Excel export,the next row or column range where cell offset 1,1 is blank; for XMLexport, a new item element. Quit if the new target instance cannot befound.
5 Write the values to the target object instance.
6 Update counters for number of items read and mark target instance ascomplete.
7 Repeat steps 4 to 6 until each instance of this data object has beenwritten.
Definition File FormatsThe import and export definition files are XML formatted data files thatdescribe how the various Aspen Flare System Analyzer data objects and theircorresponding data items should be read from or written to the supportedexternal file formats. This section of the documentation describes the layoutof these files.
Import File Formats
File Header
The top level element of an import definition file must have the tag nameFlarenetImport and contain the following attributes:
Attribute Description
LastModified This is a date string that indicates the date that the file was lastupdated.
FlarenetVersion This indicates the version of Aspen Flare System Analyzer that thefile is applicable to.
FileType This indicates the type of external file import that is described inthis definition file. Valid values are Access, Excel or XML.
A File Format 193
Data Object Elements
The child elements of the FlarenetImport tag define the various data objectsthat may be imported by Aspen Flare System Analyzer. These parent dataobject elements may contain child data object elements that describe datasubsections which may be imported from a different location to the parentdata object. For example, a pipe data object has a data subsection defined forthe PFD layout information.
A data object element has the following attributes:
Attribute Description
ObjectName This defines the source of the data object in the external file. Its usagedepends on the type of external file as follows:
Access – The entry defines a database table.
Excel – The entry defines a worksheet.
XML – The entry defines the tag name of a group element.
Import This indicates whether this object type is to be imported. Valid valuesare Yes or No.
Contained This indicates whether the data for this object is contained in the sameexternal data source as the parent object. Valid values are Yes or No.This setting is always No for a parent data object.
DataBy This entry appears in Excel import definition files only. It defines howthe data for this object is organized. Valid values are Row, Column orSheet.
StartAt This entry appears in Excel import definition files only. When DataBy isset to Row or Column, it defines the starting row or column for thedata. When DataBy is set to Sheet, it defines the tag by whichworksheets of the requisite layout can be identified.
PerItem This entry appears in Excel import definition files only. It defines thenumber of rows or columns occupied by a single instance of a dataobject, including any spacing, when DataBy is set to Row or Column.
ItemTag This entry appears in XML import definition files only. It defines theelement tag name used to identify each instance of a data object withinthe group tag name defined in the ObjectName attribute.
A list of valid Data Object elements names is given in Data Objects List.
Data Item Elements
Each data object element contains data item elements that define the locationof the individual data item in the external data source. A data item elementcontains the following attributes:
Attribute Description
Import This indicates whether the item is to be imported. Valid values are Yesor No.
194 A File Format
Attribute Description
Offset This defines the location of the data value in the external file. Its usagedepends on the type of external file, but data substitution codes can bedefined for the offset in all cases – see Data Substitution Codes.
Access – The entry defines a field within the database table forthe object.
Excel – The entry defines a cell within the worksheet for theobject. The cell is defined either by a single row or column offsetor by a row, column offset.
XML – The entry defines the tag name of an element within theitem tag element for the object.
A list of the data item elements that are recognized for each data object isgiven in Data Items List.
Export File Formats
File Header
The top level element of an export definition file must have the tag nameFlarenetExport and contain the following attributes:
Attribute Description
LastModified This is a date string that indicates the date that the file was lastupdated.
FlarenetVersion This indicates the version of Aspen Flare System Analyzer that thefile is applicable to.
FileType This indicates the type of external file export that is described in thisdefinition file. Valid values are Access, Excel or XML.
Data Object Elements
The child elements of the FlarenetExport tag define the various data objectsthat may be exported by Aspen Flare System Analyzer. These parent dataobject elements may contain child data object elements that describe datasubsections which may be exported to a different location to the parent dataobject.
A data object element has the following attributes:
Attribute Description
ObjectName This defines the name of the data object that will be created and writtento in the external file. Its usage depends on the type of external file asfollows:
Access – The entry defines a database table.
Excel – The entry defines a worksheet.
XML – The entry defines the tag name of a group element.
Export This indicates whether this object type is to be exported. Valid valuesare Yes or No.
Contained This indicates whether the data for this object is to be written to thesame external data source as the parent object. Valid values are Yes orNo. This setting is always No for a parent data object.
A File Format 195
Attribute Description
DataBy This entry appears in Excel export definition files only. It defines howthe data for this object is organized. Valid values are Row, Column orSheet.
StartAt This entry appears in Excel export definition files only. When DataBy isset to Row or Column, it defines the starting row or column for thedata. When DataBy is set to Sheet, it defines the name of theworksheet that will be copied to create a worksheet for each instance ofthe data object. This name must begin with a “%” character.
PerItem This entry appears in Excel export definition files only. It defines thenumber of rows or columns occupied by a single instance of a dataobject, including any spacing, when DataBy is set to Row or Column.
ItemTag This entry appears in XML export definition files only. It defines theelement tag name used to identify each instance of a data object withinthe group tag name defined in the ObjectName attribute.
A list of valid Data Object elements names is given in Data Objects List.
Data Item Elements
Each data object element contains data item elements that define how anindividual data item is to be written to the external data source. A data itemelement contains the following attributes:
Attribute Description
Export This indicates whether the item is to be exported. Valid values are Yesor No.
Offset This defines the location where the data value will be written in theexternal file. Its usage depends on the type of external file, but datasubstitution codes can be defined for the offset in all cases – see DataSubstitution Codes.
Access – The entry defines a field within the database table forthe object.
Excel – The entry defines a cell within the worksheet for theobject. The cell is defined either by a single row or column offsetor by a row, column offset.
XML – The entry defines the tag name of an element within theitem tag element for the object.
Type This appears in Access export definition files only. It defines the datatype of the field to be created for this item. Valid values are Text fortext strings, Long for integer values, Double for floating point values.
Length This appears in Access export definition files only. It defines the length ofthe field to be created. For fields of type Text, it defines the length ofthe text string in characters; for fields of types Long and Double, it isset to 0 and will be ignored though it must be present.
A list of the data item elements that are recognized for each data object isgiven in Data Items List.
Data Substitution Codes
As indicated in the above data substitution codes may be defined in the Offsetattribute for item import and export data items. The details of these codes areas follows:
196 A File Format
Offset Codes
The following codes are recognized and processed in the Offset attribute inboth import and export definition files.
“%ObjectName”
where ObjectName is the name of a data object element, will be replacedby a value that iterates as successive instances of that type of object areread or written for this instance of the parent data object. It is used toprovide a value that iterates through repeated data items, e.g. componentdata or pipe fitting data. ObjectName may refer to any data objectelement that is a parent of the data item. The code is usually used inconjunction with a + symbol to add the iteration value to some constantvalue.
In an Access or XML import or export definition file, the + symbol meansthat the iteration value is concatenated with the constant value. E.g.Frac+%Composition will be expanded to Frac1, Frac2 etc.
In an Excel import or export definition file, *, -, and / symbols as well asthe + symbol are recognized to combine the iteration value with aconstant value to calculate a cell address. E.g. 2,2+%Composition will beexpanded to the cell references 2,3 then 2,4 etc. See the CurveMassFlowdata item in the TipCurveData data object in the definition fileDefExcel.fni for a more complicated example.
“#ObjectName”
where ObjectName is the name of a data object element, will be replacedby the total number of instances of that type of data object that havebeen read. ObjectName may refer to any data object element that is achild of the current data object element. The value returned is usuallycombined with some constant value through a + or other symbols as forthe “%ObjectName” code.
“?Composition”
is a special code that is used exactly as it stands. “?Composition” will bereplaced by each component name or offset in turn as successivecomponent composition data items are read or written. It is generallyused in conjunction with a + symbol to each component name or offset tosome constant value.
In an Access or XML import or export definition file, ?Composition willreturn component names in turn from the master component list. e.g.Frac+?Composition will be evaluated as FracMethane, FracEthane etc.
In an Excel import or export definition, ?Composition will return the indexnumber of a component in the master component list to allow it to beused to calculate a cell offset.
In both cases, the master component list is the union of the componentsin the current Aspen Flare System Analyzer case and the import or exportdefinition files. Essentially this code allows unambiguous specification of acomponent identity when merging of the component lists between a AspenFlare System Analyzer case and an import or export definition file.
A File Format 197
Recognized Objects and Items
Data Objects List
Data object elements for the following data objects and sub-sections arerecognized in import and export definition files.
Element Tag Sub Section DataObject Elements
Description
Components None Component data
BIPs None Binary interaction parameters
Connectors PFDLayout Connector nodes
ControlValves PFDLayout
Composition
SourceData
Control valve source nodes
FlowBleeds PFDLayout Flow bleed nodes
HorizontalSeparators Composition
PFDLayout
Horizontal separator nodes
OrificePlates PFDLayout Orifice plate nodes
Fitting None Fitting data for pipes
Pipes PFDLayout
Fitting
Pipes
ReliefValves PFDLayout
SourceData
Relief valve source nodes
Tees PFDLayout Tee nodes
FlareTips PFDLayout
Curves
Flare tip nodes
Curves Points Tip pressure drop curves
Points None Data points in tip pressure drop curve
VerticalSeparators PFDLayout Vertical separator nodes
Solvers None Solver options
Scenarios SourceData Scenario data
Composition None Component composition data
SourceData Composition Scenario specific source data
PFDLayout None PFD layout information
Results Phase Summary results data for each pipe.Export definition files only.
Phase CompResults Properties for each phase at each end ofeach pipe. Export definition files only.
CompResults None Composition results for each pipe. Exportdefinition files only.
Data Items List
The data items that can be read for each data object are as follows:
198 A File Format
Components
Attribute Description
Hypothetical The hypothetical components
Name The component name
Id The component ID number
Type The component type
Formula The component formula
MolWt The component molecular weight
NBP The component normal boiling point (K)
StdDensity The component standard density (kg/m3)
WatsonK The component Watson K value
Pc The component critical pressure (bar a)
Tc The component critical temperature (K)
Vc The component critical volume (m3/kgmole)
Vchar The component characteristic volume (m3/kgmole)
Omega The component acentric factor
OmegaSRK The component SRK acentric factor
Ha The enthalpy A coefficient (kJ/kgmole)
Hb The enthalpy B coefficient (kJ/kgmole/K)
Hc The enthalpy C coefficient (kJ/kgmole/K2)
Hd The enthalpy C coefficient (kJ/kgmole/K3)
He The enthalpy C coefficient (kJ/kgmole/K4)
Hf The enthalpy C coefficient (kJ/kgmole/K5)
S The entropy coefficient
ViscA The viscosity A parameter
ViscB The viscosity B parameter
HeatOFCombustion The heat of combustion
NBPValue The value of normal boiling point
PcValue The value of critical pressure
TcValue The value of critical temperature
BIPs
Attribute Description
PropPkg The code for the property package:
0 – Vapor pressure
1 – Peng Robinson
2 – Soave Redlich Kwong
3 – Compressible Gas
Comp1 The name of the first component
Comp2 The name of the second component
Kij12 Value of interaction parameter for comp1 / comp2
Kij21 Value of interaction parameter for comp2 / comp1
A File Format 199
Connectors
Attribute Description
FittingLossMethod Code for the fitting loss method: 0 = ignored, 1 =calculated
IsothermalDPOption Code for enabling isothermal pressure dropcalculations: 0 = No, 1 = Yes
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 = Yes
SwageMethod Code for size change calculation method: 0 =Compressible, 1 = Incompressible, 2 = Transition
CompressibleTransition DP percent of inlet pressure for transition (%)
Length Length of the swage (mm)
Angle The internal angle of the swage (radians)
ChokeMethod Choke flow check
MaxConnectionCount Maximum possible connection count
DescribeCalculations Describe calculations
Name The connector name
Location The location text
Ignore The ignored flag: 0 = not ignored, 1=ignored
UpstreamConnection The name of the upstream pipe
UpstreamConnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
DownstreamConnnection The name of the downstream pipe
DownstreamConnnectionAt Code for the downstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
ControlValves
Attribute Description
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Ignore Ignore flag
KMultiply Fittings loss Ft factor for inlet pipe
KOffset Fittings loss offset for inlet pipe
FlangeDiameter Internal diameter of flange (mm)
ElevationChange The elevation change of the inlet piping (m)
Length The length of the inlet piping (m)
InternalDiameter The inlet pipe diameter (mm)
Schedule The inlet pipe schedule
NominalDiameter The inlet pipe nominal diameter
Roughness The inlet pipe roughness (mm)
Material The code for the inlet pipe material: 0 = CarbonSteel, 1 = Stainless steel
Thickness Code for the thickness of the pipe wall
UsePipeClass Code for enabling pipe class usage: 0 = No, 1 =Yes
Name The control valve name
200 A File Format
Attribute Description
Location The location text
UpstreamConnnection The name of the upstream pipe
UpstreamConnnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
FlowBleeds
Attribute Description
OfftakeMultiplier Flow bleed multiplier
OfftakeOffset Bleed flow offset (kg/h)
OfftakeMinimum Minimum bleed flow (kg/h)
OfftakeMaximum Maximum bleed flow (kg/h)
PressureDrop Pressure drop over bleed (bar)
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Name The flow bleed name
Location The location text
Ignore The ignored flag: 0 = not ignored, 1=ignored
UpstreamConnection The name of the upstream pipe
UpstreamConnectionAt Code for the upstream pipe connection point
0 = upstream end, 1 = downstream end
DownstreamConnnection The name of the downstream pipe
DownstreamConnnectionAt Code for the downstream pipe connection point
0 = upstream end, 1 = downstream end
ConnectedCount Connection count
HorizontalSeparators
Attribute Description
LiquidLevel The liquid level (mm)
Diameter The vessel diameter (mm)
FittingLossMethod Code for fittings loss calculation: 0 = Ignored, 1 =Calculated
IsothermalPressureDrop Code for enabling isothermal pressure dropcalculations: 0 = No, 1 = Yes
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 = Yes
SwageMethod Code for size change calculation method: 0 =Compressible, 1 = Incompressible, 2 = Transition
CompressibleTransition DP percent of inlet pressure for transition (%)
BodyDimension Code for body area usage: 0 = Full body area, 1 =Partial body area on flow
ChokeMethod Choke flow check
CannotTear Cannot tear
DesignLength Design length
Ddrop Ddrop
A File Format 201
Attribute Description
DrainVol Drain volume
Holduptime Holdup time
Vsettling V settling
IsTear Is tear
PresBody Body pressure
TempBody Body temperature
VelBody Body velocity
DenBody Body density
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Name The horizontal separator name
Ignore The ignored flag: 0 = not ignored, 1=ignored
Location The location text
UpstreamConnection The name of the upstream pipe
UpstreamConnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
BranchstreamConnection The name of the branch stream pipe
BranchstreamConnectionAt Code for the branch stream pipe connection point: 0 =upstream end, 1 = downstream end
DownstreamConnection The name of the downstream pipe
DownstreamConnectionAt Code for the downstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
OrificePlates
Attribute Description
FittingLossMethod Code for pressure loss method: 0 = Ignored, 1 = ThinPlate, 2 = Contraction/Expansion
IsothermalPressureDrop Code for enabling isothermal pressure drop calculations:0 = No, 1 = Yes
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 = Yes
SwageMethod Code for size change calculation method: 0 =Compressible, 1 = Incompressible, 2 = Transition=
CompressibleTransition DP percent of inlet pressure for transition (%)
DownstreamDiameterRatio Ratio of orifice to downstream diameter
UpstreamDiameterRatio Ratio of orifice to upstream diameter
Diameter Diameter of orifice (mm)
ChokeMethod Choke flow check
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Name The orifice plate name
Location The location text
Ignore The ignored flag: 0 = not ignored, 1=ignored
UpstreamConnection The name of the upstream pipe
202 A File Format
Attribute Description
UpstreamConnectionAt The code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
DownstreamConnnection The name of the downstream pipe
DownstreamConnnectionAt The code for the downstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
Pipes
Attribute Description
LimitReached Reached limit or not
TailPipe Code to identify tailpipe: 0 = No, 1 = Yes
Sizeable Code for indicating sizeable pipe: 0 = No, 1 = Yes
UsePipeClass Code for pipe class usage: 0 = No, 1 = Yes
WallThickness Pipe wall thickness (mm)
InternalDiameter Pipe internal diameter (mm)
Schedule Pipe schedule
NominalDiameter Pipe nominal diameter
ThermalConductivity Pipe material thermal conductivity (W/m/C)
Roughness Pipe absolute roughness (mm)
Material Code for pipe material: 0 = Carbon steel, 1 =Stainless steel
ElevationChange Pipe elevation change (m)
Length Pipe length (m)
FittingsLossMultiply Fittings loss Ft factor
FittingsLossOffset Fittings loss offset
LengthMultiplier Multiplier for pipe length
MultipleElementCalculation Code for the multiple element heat transfercalculation: 0 = No, 1 = Yes
Emissivity The material fractional emissivity
ExternalRadiativeHTC Code for including radiative heat transfer: 0 = No, 1= Yes
HeatTransferEnabled Code to enable heat transfer calculations: 0 = No, 1= Yes
WindVelocity Wind speed (m/s)
Temperature Temperature outside pipe (C)
InsulationThermalConductivity Insulation thermal conductivity (W/m/C)
Thickness Insulation thickness (mm)
InsulationName Insulation description
Duty Duty (kJ/h)
OutletTemperatureSpecification Temperature leaving pipe (C)
DampingFactor Damping factor
VLEMethod Code for VLE method: 0 = Default, 1 = CompressibleGas, 2 = Peng Robinson, 3 = Soave Redlich Kwong,4 = Vapor Pressure
A File Format 203
Attribute Description
StaticHeadContribution Code for the static head contribution: 0 = Include, 1= Ignore Downhill Recovery, 2 = Ignore
FrictionFactorMethod Code for friction factor method: 0 = Default, 1 =Round, 2 = Chen
Elements Number of elements for pipe calculation
VerticalPipe Code for DP method for vertical pipes: 0 = Default, 1= Isothermal gas, 2 – Adiabatic gas, 3 =Beggs&Brill, 4 = Dukler, 5 = Orkisewski
InclinedPipeMethod Code for DP method for inclined pipes: 0 = Default,1 = Isothermal gas, 2 – Adiabatic gas, 3 =Beggs&Brill, 4 = Dukler
HorizontalPipeMethod Code for DP method for horizontal pipes: 0 =Default, 1 = Isothermal gas, 2 – Adiabatic gas, 3 =Beggs&Brill, 4 = Dukler
ExternalMedium Code for the external medium: 0 = Air, 1 = SeaWater
RoughnessForFitting Roughness for fitting
Klocked K locked
Kusing K using
CalcStatus Calculation status
FittingCount Number of fittings linked to this pipe
PhysicalLength Physical length
MaxConnectionCount Maximum possible connection count
Name Name
Ignore The ignored flag: 0 = not ignored, 1=ignored
Location The location text
DescribeCalculations Describe calculations
UpstreamConnection The name of the upstream node
UpstreamConnectionAt Code for the upstream node connection point: 0,1,2depending on upstream node
DownstreamConnnection The name of the downstream node
DownstreamConnnectionAt Code for the downstream pipe connection point:0,1,2 depending on downstream node
ConnectedCount Connection count
Fitting
Attribute Description
ItemName The name of the fitting
ID Description of the fitting
KOffset Fitting loss constant
KMultiplier Fitting loss Ft factor
ReliefValves
Attribute Description
MAWP Maximum allowable working pressure (bar a)
204 A File Format
Attribute Description
MechPres Mechanical pressure limit (bar a)
ValveType Type code for valve: 0 = Balanced, 1 =Conventional
OrificeType Standard type code for orifice
ValveArea Area of each valve orifice (mm2)
ValveCount Number of valves
IsenTropicFlash Isentropic flash
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Ignore Ignore flag
KMultiply Fittings loss Ft factor for inlet pipe
KOffset Fittings loss offset for inlet pipe
FlangeDiameter Internal diameter of flange (mm)
ElevationChange The elevation change of the inlet piping (m)
Length The length of the inlet piping (m)
InternalDiameter The inlet pipe diameter (mm)
Schedule The inlet pipe schedule
NominalDiameter The inlet pipe nominal diameter
Roughness The inlet pipe roughness (mm)
Material Code for the inlet pipe material: 0 = Carbon Steel,1 = Stainless steel
Thickness Thickness
UsePipeClass Code for enabling pipe class usage: 0 = No, 1 =Yes
Name The relief valve name
Location The location text
UpstreamConnnection The name of the upstream pipe
UpstreamConnnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
Tees
Attribute Description
Body Code for body type: 0 = Run, 1 = Tail, 2 = Branch, 3= Auto
Theta Code for branch angle: 0 = 30 deg, 1 = 45 deg, 2 =60 deg, 3 = 90 deg
ThetaAsReal Theta as real
FittingLossMethod Code for fittings loss calculation: 0 = Ignored, 1 =Simple, 2 = Miller
MillerChartExtrapolation Code for Miller chart extrapolation: 0 = None, 1 =Miller Ratio Squared, 2 = Gardel
ConnectorIfIncomplete Code to use connector calculation: 0 = No, 1 = Yes
IsothermalPressureDrop Code for enabling isothermal pressure dropcalculations: 0 = No, 1 = Yes
A File Format 205
Attribute Description
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 =Yes
SwageMethod Code for size change calculation method: 0 =Compressible, 1 = Incompressible, 2 = Transition
CompressibleTransition DP percent of inlet pressure for transition (%)
BodyDimension Code for body area usage: 0 = Full body area, 1 =Partial body area on flow
ChokeMethod Choke flow check
Orientation Orientation
Separate Separate
CannotTear Cannot tear
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Name The tee name
Location The location text
Ignore The ignored flag: 0 = not ignored, 1=ignored
UpstreamConnection The name of the upstream pipe
UpstreamConnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
BranchstreamConnection The name of the branch stream pipe
BranchstreamConnectionAt Code for the branch stream pipe connection point: 0= upstream end, 1 = downstream end
DownstreamConnection The name of the downstream pipe
DownstreamConnectionAt Code for the downstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
FlareTips
Attribute Description
Diameter Diameter of flare (mm)
CompressibleTransition DP percent of inlet pressure for transition (%)
Method Method
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 = Yes
IsothermalPressureDrop Code for enabling isothermal pressure drop calculations:0 = No, 1 = Yes
FittingLossCoefficient Fittings loss coefficient
FittingLossCoefficientBasis Code for fittings loss basis: 0 = Total pressure, 1 =static pressure
UseCurves Code for curve usage: 0 = No, 1 = Yes
NumCurves Number of pressure drop curves
FlowExtrapolation Flow extrapolation
MolWtExtrapolation Molecular weight extrapolation
PressureCorrection Pressure correction
RefTemp Reference temperature for curve data (C)
Sizeable Code for indicating sizeable pipe
206 A File Format
Attribute Description
UsePipeClass Code for enabling Pipe Class usage
WallThickness Wall thickness
InternalDiameter Internal diameter
Schedule Pipe schedule
NominalDiameter Pipe nominal diameter
ThermalConductivity Pipe material thermal conductivity (W/m/C)
Roughness Pipe roughness
Material Code for the inlet pipe material
ChokeMethod Choke flow check
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Name The flare tip name
Location The location text
Ignore The ignored flag: 0 = not ignored, 1=ignored
UpstreamConnection The name of the upstream pipe
UpstreamConnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
Curves
Attribute Description
TipName The name of the top (30 chars)
MolWt The reference molecular weight for the curve
CurveNumPoints The number of points in the curve
Points
Attribute Description
CurveDataPointNo The number of the curve data point
MolWt The mole weight of the curve
MassFlow The mass flow for the curve data point (kg/h)
PresDrop The pressure drop for the curve data point (bar)
VerticalSeparators
Attribute Description
Diameter The vessel diameter (mm)
FittingLossMethod Code for fittings loss calculation: 0 = Ignored, 1 =Calculated
IsothermalPressureDrop Code for enabling isothermal pressure drop calculations:0 = No, 1 = Yes
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 = Yes
SwageMethod Code for size change calculation method: 0 =Compressible, 1 = Incompressible, 2 = Transition
CompressibleTransition DP percent of inlet pressure for transition (%)
A File Format 207
Attribute Description
ChokeMethod Choke flow check
DesignDiameter Design diameter
Ddrop Ddrop
Vsettling V settling
PresBody Body pressure
TempBody Body temperature
VelBody Body velocity
DenBody Body density
DescribeCalculations Describe calculations
MaxConnectionCount Maximum possible connection count
Name The vertical separator name
Location The location text
Ignore The ignored flag: 0 = not ignored, 1=ignored
UpstreamConnection The name of the upstream pipe
UpstreamConnectionAt Code for the upstream pipe connection point: 0 =upstream end, 1 = downstream end
DownstreamConnection The name of the downstream pipe
DownstreamConnectionAt Code for the downstream pipe connection point: 0 =upstream end, 1 = downstream end
ConnectedCount Connection count
Scenarios
Attribute Description
Name The scenario name (30 chars)
OptionVelConstr Option velocity constraint
Done Done
HeaderMach Header mach number limit
HeaderVapVel Header vapor velocity limit (m/s)
HeaderLiqVel Header liquid velocity limit (m/s)
HeaderRV2 Header momentum limit (kg/m/s2)
HeaderNoise Header noise limit (dB)
TailPipeMach Tailpipe mach number limit
TailPipeVapVel Tailpipe vapor velocity limit (m/s)
TailPipeLiqVel Tailpipe liquid velocity limit (m/s)
TailPipeRV2 Tailpipe momentum limit (kg/m/s2)
TailPipeNoise Tailpipe noise limit (dB)
Pressure System back pressure (bar a)
CalculateMe Calculate me
SolverOptions
Attribute Description
AmbientTemperature External temperature (C)
AtmosphericPressure Atmospheric pressure (bar a)
208 A File Format
Attribute Description
CheckChoke Check for choke flow: 0 = No, 1 = Yes
Choke Code for choke calculation method: 0 = Simple, 1 =HEM
HeatTransfer Enable heat transfer calculations: 0 = No, 1 = Yes
ExternalRadiation External radiation
Mode Code for calculation mode: 0 = Rating, 1 = Design, 2= Debottleneck
RatedFlow Use rated flow for inlet pipes
RatedFlowNodes Use rated flow for downstream nodes attached totailpipes
RatedFlowTailPipe Use rated flow for tailpipes: 0 = No, 1 = Yes
WindSpeed Wind velocity (m/s)
UseKineticEnergy Include kinetic energy: 0 = No, 1 = Yes
IgnoreSepKineticEnergy Ignore kinetic energy in separators: 0 = No, 1 - Yes
KineticEnergyBasis Code for kinetic energy basis: 0 = Inlet Pipe Velocity,1 = Zero velocity
CalcIgnoredSources Calculate ignored sources as zero flow: 0 = No, 1 =Yes
MabpForInactiveValves Check MABP for inactive sources: 0 = No, 1 = Yes
IgnoreSourceSizeChangeWhenSizing
Ignore valve flange size change in design calculations:0 = No, 1 = Yes
MaxmumSystemVelocity Maximum system velocity
AllScenarios Code to indicate which scenarios are calculated: 0 =Current, 1 = All, 2 = Selected
VLE Code for VLE method: 0 = Compressible gas, 1 =Peng Robinson, 2 = Soave Redlich Kwong, 3 = VaporPressure
Enthalpy Code for enthalpy method: 0 = Ideal gas, 1 =PengRobinson, 2 = Soave Redlich Kwong, 3 = LeeKesler
VleSourceOutletTemp VLE source outlet temperature
EnthalpySourceOutletTemp Enthalpy source outlet temperature
Horizontal Code for horizontal pressure drop method: 0 =Isothermal gas, 1 = Adiabatic Gas, 2 = Beggs&Brill 3= Dukler
Inclined Code for inclined pressure drop method: 0 =Isothermal gas, 1 = Adiabatic Gas, 2 = Beggs&Brill 3= Dukler
Vertical Code for vertical pressure drop method: 0 =Isothermal gas, 1 = Adiabatic Gas, 2 = Beggs&Brill 3= Dukler, 4 = Orkisewski
Elements Number of elements for two phase calculations
FrictionFactor Code for friction factor method: 0 = Round, 1 = Chen
UsePipeRoughnessForFitting Use pipe roughness for fitting
RoughnessForFitting Roughness for fitting
WarnMachForSizing Warn Mach for sizing
WarnVelocityForSizing Warn velocity for sizing
WarnRhoV2ForSizing Warn RhoV2 for sizing
A File Format 209
Attribute Description
WarnNoiseForSizing Warn noise for sizing
WarnIceFormForSizing Warn Ice form for sizing
WarnBPForSizing Warn BPF for sizing
WarnChokeForSizing Warn choke flow for sizing
WarnSlugForSizing Warn slug flow for sizing
WarnTempForSizing Warn temperature for sizing
WarnPressureBasis Warn pressure basis
WarnPhysPropFailure Warn physical properties failure
WarnHeatBalanceFailure Warn heat balance failure
WarnChokePresFailure Warn choke pressure failure
WarnPresDropFailure Warn pressure drop failure
WarnLiqWithVapMethodFailure
Warn liquid with vapour only method failure
WarnCorrRangeFailure Warn correlation out of range failure
WarnInitWhileSizing Warn initialization while sizing
WarnSizeChangeWhileSizing Warn size change while sizing
WarnLimitReachedWhileSizing
Warn limit reached while sizing
PresTolProperties Pressure tolerance in properties loop (%)
PresTolUnitOp Pressure tolerance for unit operation calculations (%)
PresTolLoop Pressure tolerance for loop calculations (%)
MassToLoop Mass balance tolerance in outer loop (%)
IterationsProperties Number of iterations in inner (properties) loop
IterationsLoop Number of iterations for loop calculations
DamperProperties Damping factor for inner (properties) loop
DamperLoop Damping factor for loop calculations
LoopMethod Select loop convergence method: 0=Newton Raphson,1=Broyden, 2=Force Convergent
LoopAnalyser Select analyzer for looped systems: 0 = Convergent, 1= Simultaneous
EchoLoops Are loop calculations echoed: 0 = No, 1 = Yes
KeepBad Keep bad
UpdateEstimates Update flow estimates from solution: 0 = No, 1 = Yes
InitalPressure Initial pressure for property calculations (bar a)
LengthMultiplier Pipe length multiplication factor
InitPhaseMethodForSizing Initialization phase method for sizing
UpstreamMinTemp Upstream minimum temperature
DownstreamMinTemp Downstream minimum temperature
UpstreamMaxTemp Upstream maximum temperature
DownstreamMaxTemp Downstream maximum temperature
InletFlowCheck Inlet flow check
GaugeInletCheck Gauge inlet check
IgnoreInlet Ignore inlet
210 A File Format
SourceData
Attribute Description
ScenarioName The name of the scenario
SourceName The name of the source
MassFlow Mass flow of the source (kg/h)
Ignored The ignored flag: 0 = not ignored, 1=ignored
PresAllow Allowable pressure
OutletTemperature Outlet temperature (C)
InletTemp Inlet temperature
InletTempSpec Inlet specified temperature value (C)
InletPressure Inlet pressure
LockMABP Auto update of MABP: 0 = No, 1 = Yes
VLEMethod Code for VLE method: 0 = Model default, 1 =Compressible gas, 2 = Peng Robinson, 3 = SoaveRedlich Kwong, 4 = Vapor Pressure
FittingLossMethod Code for fitting loss calculation: 0 = Ignored, 1 =Calculated
IsothermalPressureDrop Code for enabling isothermal pressure dropcalculations: 0 = No, 1 = Yes
TwoPhaseCorrection Code for two phase correction option: 0 = No, 1 =Yes
SwageMethod Code for size change calculation method: 0 =Compressible, 1 = Incompressible, 2 = Transition
CompressibleTransition DP percent of inlet pressure for transition (%)
VapourFraction Vapour fraction
VapourMolWt Vapour molecular weight
IsentropicEfficiency Isentropic efficiency
SizingMethod Code for PSV sizing method: 0 = API, 1 = HEM
BackPressure Back pressure
MultiPhaseCd Multi-phase Cd
LiquidCd Liquid Cd
Kb Kb
RuptureDisk Rupture disk
PresCalc Static pressure
DenCalc Calculated density
VelCalc Velocity
TempCalc Temperature
ChokeMethod Choke flow check
Energy Energy
Enthalpy Enthalpy
Entropy Entropy
Quality Quality
Tempincalc Calculated inlet temperature
SonicCalc Calculated sonic
NonRecoverablePresDrop Piping non-recoverable pressure drop
InletVelocity Inlet velocity
A File Format 211
Attribute Description
InletDensity Inlet density
StaticPresDrop Static pressure drop
TotalPresDrop Total pressure drop
HasProblem Has problem flag
HeaderVapourFraction Header vapour fraction
HeaderVapourMolWt Header vapour molecular weight
HasProblemDp Constraint violation: pressure drop
HasProblemVel Constraint violation: velocity
HasProblemMach Constraint violation: Mach number
HasProblemChoke Constraint violation: choke
HasProblemRhoV2 Constraint violation: RhoV2
HasProblemPres Constraint violation: pressure
HasProblemTemp Constraint violation: temperature
VfCalc Vf calculation
StagnationEnthalpy Stagnation enthalpy
StagnationEnthalpyCalc Calculated stagnation enthalpy
FlowPathCount Flow path count
FlowPathName Flow path name
FlowPathType Flow path type
RatedFlow Rated flow of the source (kg/h)
Contingency Code for sizing contingency: 0 = Operating, 1 = Fire
LockRatedFlow Auto update of rated flow: 0 = No, 1 = Yes
LockReliefPressure Auto update of relieving pressure: 0 = No, 1 = Yes
CpCvRatio Cp Cv ratio
Compressibility Compressibility
InletPresTotalCalc Total inlet pressure
PresTotalCalc Total pressure
MachNo Mach number
RhoV2Calc Rho V2
MolarFlow Molar flow
MolWt Fluid molecular weight
StaticPresDropForSummary Valve static pressure drop
TotalPresDropForSummary Valve total pressure drop
Composition
Attribute Description
ScenarioName The name of the scenario
SourceName The name of the source
FluidType Fluid type
Basis Code for composition input basis: 0 = MolWt, 1 = Molefraction, 2 = Mass fraction
MolWt Molecular weight
212 A File Format
PFDLayout
Attribute Description
ItemName The name of the PFD item
XPosition The X coordinate of the item
YPosition The Y coordinate of the item
LabelXPosition The X coordinate of the item label
LabelYPosition The X coordinate of the item label
RotationFlipType Code for icon rotation: 0 = None, 1 = Rotate 90°, 2 = Rotate180°, 3 = Rotate 270°, 4 = Flip X, 5 = Rotate 90° + Flip Y, 6 =Flip Y, 7 = Rotate 90° + Flip X
Results
Attribute Description
ScenarioName The name of the scenario
SegmentName The name of the pipe segment
MolWt Molecular weight
MolarFlow Molar weight
MassFlow The mass flow (kg/h)
UpstreamTestFlow Test flow of upstream
DownstreamTestFlow Test flow of downstream
dp_F Pressure drop due to friction (bar)
dp_A Pressure drop due to acceleration (bar)
dp_E Pressure drop due to elevation change (bar)
dp Pressure drop
Noise Noise (dB)
HtcInternal Internal heat transfer coefficient (W/m2/C)
HtcConvExternal External heat transfer coefficient (W/m2/C)
HtcOverall Overall heat transfer coefficient (W/m2/C)
UpstreamVelocityNonRated Upstream non-rated velocity
DownstreamVelocityNonRated Downstream non-rated velocity
UpstreamVelocityRated Upstream rated velocity
DownstreamVelocityRated Downstream rated velocity
UpstreamVelocity Velocity at upstream end of pipe (m/s)
DownstreamVelocity Velocity at downstream end of pipe (m/s)
UpstreamSonicVelocity Upstream sonic velocity
DownstreamSonicVelocity Downstream sonic velocity
UpstreamPresTotalNonRated Upstream total non-rated pressure
DownstreamPresTotalNonRated Downstream total non-rated pressure
UpstreamPresTotalRated Upstream total rated pressure
DownstreamPresTotalRated Downstream total rated pressure
UpstreamPresTotal Upstream total pressure
DownstreamPresTotal Downstream total pressure
UpstreamPresStatic Upstream static pressure
DownstreamPresStatic Downstream static pressure
A File Format 213
Attribute Description
UpstreamTemperature Temperature at upstream end of pipe (C)
DownstreamTemperature Temperature at downstream end of pipe (C)
UpstreamEnthalpy Energy at upstream end of pipe (kJ/kgmole)
DownstreamEnthalpy Energy at downstream end of pipe (kJ/kgmole)
UpstreamDensity Density at upstream end of pipe (kg/m3)
DownstreamDensity Density at downstream end of pipe (kg/m3)
UpstreamFlowRegime Flow regime at upstream end of pipe
DownstreamFlowRegime Flow regime at downstream end of pipe
CanCalc Can calculate
Duty Heat transferred (kJ/h)
FrictionFactor Friction factor
Dp_Fittings Pressure drop due to fittings (bar)
RatedFlow The rated flow (kg/h)
ReynoldsNonRated Reynolds non-rated
ReynoldsRated Reynolds rated
Reynolds Reynolds number
SourcePres Pressure of attached source node (bar a)
Equivlength Equivalent length (m)
UpstreamEnergy Energy at upstream end of pipe (kJ/h)
DownstreamEnergy Energy at downstream end of pipe (kJ/h)
UpstreamEnthalpyEnergy Upstream enthalpy energy
DownstreamEnthalpyEnergy Downstream enthalpy energy
UpstreamMachNoNonRated Upstream non-rated Mach number
DownstreamMachNoNonRated Downstream non-rated Mach number
UpstreamMachNoRated Upstream rated Mach number
DownstreamMachNoRated Downstream rated Mach number
UpstreamMachNo Mach number at upstream end of pipe
DownstreamMachNo Mach number at downstream end of pipe
UpstreamPresProp Upstream pressure property
DownstreamPresProp Downstream pressure property
UpstreamRhoV2NonRated Upstream non-rated Rho V2
DownstreamRhoV2NonRated Downstream non-rated Rho V2
UpstreamRhoV2Rated Upstream rated Rho V2
DownstreamRhoV2Rated Downstream rated Rho V2
UpstreamRhoV2 Momentum at upstream end of pipe (kg/m/s2)
DownstreamRhoV2 Momentum at downstream end of pipe (kg/m/s2)
UpstreamVapourFraction Upstream vapour fraction
DownstreamVapourFraction Downstream vapour fraction
UpstreamProbChoked Upstream probable choked
DownstreamProbChoked Downstream probable choked
UpstreamProbMachNo Upstream probable Mach number
DownstreamProbMachNo Downstream probable Mach number
ProbNoise Probable noise
214 A File Format
Attribute Description
ProbSourcePres Probable source pressure
ProbSource Probable source
UpstreamProbRhoV2 Upstream probable Rho V2
DownstreamProbRhoV3 Downstream probable Rho V2
ProbSlugs Probable slug flows
UpstreamProbTemp Upstream probable temperature
DownstreamProbTemp Downstream probable temperature
UpstreamProbVelLiq Upstream probable liquid velocity
DownstreamProbVelLiq Downstream probable liquid velocity
UpstreamProbVelVap Upstream probable vapour velocity
DownstreamProbVelVap Downstream probable vapour velocity
PresBody Body pressure
DenBody Body density
VelBody Body velocity
Estimate Estimate
CannotTear Cannot tear
WallTemperature Temperature of pipe wall (C)
MaxStep Maximum step
MaxFlow Maximum flow
MinFlow Minimum flow
HtcRadExt External radiative HTC
ExtTemperature External temperature
UpstreamVelLiqNonRated Upstream non-rated liquid velocity
DownstreamVelLiqNonRated Downstream non-rated liquid velocity
UpstreamVelLiqRated Upstream rated liquid velocity
DownstreamVelLiqRated Downstream rated liquid velocity
UpstreamVelLiq Upstream liquid velocity
DownstreamVelLiq Downstream liquid velocity
UpstreamVelVapNonRated Upstream non-rated vapour velocity
DownstreamVelVapNonRated Downstream non-rated vapour velocity
UpstreamVelVapRated Upstream rated vapour velocity
DownstreamVelVapRated Downstream rated vapour velocity
UpstreamVelVap Upstream vapour velocity
DownstreamVelVap Downstream vapour velocity
PresDrop Pressure drop over pipe (bar)
UpstreamPressure Pressure at upstream end of pipe (bar a)
DownstreamPressure Pressure at downstream end of pipe (bar a)
TotalPresDrop Total pressure drop
EquivlengthForPipeSummary Equivalent length
Phase
Attribute Description
ScenarioName The name of the scenario
A File Format 215
Attribute Description
SegmentName The name of the pipe segment
SegmentEnd End of the pipe segment
Phase Phase description
Density Density of the phase (kg/m3)
Enthalpy Energy of the phase (kJ/kgmole)
Entropy Entropy of the phase (kJ/kgmole/K)
Fraction Fraction of the phase
HeatCap Heat capacity of the phase (kJ/kgmole/K)
MolWt Mol Wt of the phase
SurfTen Surface tension of the phase (dyne/cm)
ThermCond Thermal conductivity of the phase (W/m/K)
Viscosity Viscosity of the phase (cP)
ZFactor Z Factor of the phase
CompResults
Attribute Description
ScenarioName The name of the scenario
SegmentName The name of the pipe segment
FluidType Fluid type
Basis Basis
MolWt The molecular weight of the fluid
Fraction The mole fraction of each component
Report File FormatsThe printouts can be customized to a limited extent using a XML file with theextension “.xml”. This file may be edited using any ASCII text editor such asthe NOTEPAD application distributed with Microsoft Windows.
The default “.xml” file for the printed reports is: ReportFormat.xml
By default, the report format file is located in the Aspen Flare SystemAnalyzer program directory. You can change the location and “.xml“ file forthe reports on the Reports tab on the Preferences Editor.
216
Fig A.1
The following defines which variable may be printed with each report:
Variable Name
ambient
backpres
basis
class
conductivity
connections
densitydown
densityup
description
dsn
duty
elevation
energy
energyflowdown
The following defines which variable may be printed with each report:
Variable Description
Ambient temperature
Back pressure
Composition basis
Pipe class
Thermal conductivity
Item connections
Downstream density
Upstream density
Description
Downstream node
Heat loss
Elevation change
Energy
Downstream energy flow
A File Format
The following defines which variable may be printed with each report:
A File Format 217
Variable Name Variable Description
energyflowup Upstream energy flow
enthalpy Enthalpy
enthalpyflowdown Downstream enthalpy flow
enthalpyflowup Upstream enthalpy flow
enthalpyup Upstream enthalpy
enthalpydown Downstream enthalpy
entropy Entropy
entropydown Downstream entropy
entropyup Upstream entropy
equivlength Equivalent length
exttemperature External temperature
fittinglist Fitting list
fittingsa Fitting loss A
fittingsb Fitting loss B
flange Flange diameter
fractiondown Downstream phase fraction
fractionup Upstream phase fraction
frictionfractor Friction factor
group Item group
headmach Header mach number
headvelvap Header vapor velocity
headvelliq Header liquid velocity
headrhov2 Header rho V2
headnoise Header noise
heatcapdown Downstream heat capacity
heatcapup Upstream heat capacity
hia Enthalpy A coefficient
hib Enthalpy B coefficient
hic Enthalpy C coefficient
hid Enthalpy D coefficient
hie Enthalpy E coefficient
hif Enthalpy F coefficient
htcradext External radiative HTC
htcoverall Overall HTC
htcexternal External HTC
htcinternal Internal HTC
id Item ID
ignored Item ignored
inletlength Inlet pipe length
218 A File Format
Variable Name Variable Description
inletelevation Inlet pipe elevation change
inletmaterial Inlet pipe material
inletroughness Inlet pipe roughness
inletnominal Inlet pipe nominal diameter
inletschedule Inlet pipe schedule
inletinternal Inlet pipe internal diameter
inletclass Inlet pipe class
Inletfittingsa Inlet pipe fitting loss A
Inletfittingsb Inlet pipe fitting loss B
insname Insulation description
insthick Insulation thickness
insconductivity Insulation conductivity
internal Internal diameter
length Segment length
lmultiply Length multiplier
location Segment location
machdown Downstream mach number
machup Upstream mach number
massflow Mass flow
material Material of construction
methoddamping Damping factor
methodelements Two phase elements
methodfriction Friction factor
methodfitlos Fitting loss method
methodhordp Horizontal 2 phase pressure drop method
methodincdp Inclined pressure drop
methodverdp Vertical 2 phase pressure drop method
methodvle VLE method
molarflow Molar flow
molwt Molecular weight
molwtdown Downstream molecular weight
molwtup Upstream molecular weight
multiply Fittings equation multiplier
name Item name
nbp Normal boiling point
node Node
nodetype Node type
noise Noise
nominal Nominal pipe diameter
A File Format 219
Variable Name Variable Description
number Index number
offset Fittings equation offset
omega Acentric factor
omegasrk SRK acentric factor
orificearea Orifice area
orifice Orifice
pc Critical pressure
phase Phase label
pressource Static source back pressure
presallow Allowable back pressure
presdown Downstream static pressure
presdrop Pressure drop
presdropfriction Static pipe friction loss
presdropacceleration Static pipe acceleration loss
presdropelevation Static pipe elevation loss
presdropfittings Static pipe fitting loss
presin Inlet pressure
preslimit Back pressure limit
presup Upstream static pressure
ratedflow Rated mass flow
refer Literature reference
regime Flow regime
resize Resizable flag
reynolds Reynolds number
rhov2up Upstream rho V2
rhov2down Downstream rho V2
roughness Wall roughness
schedule Pipe schedule
si Entropy coefficient
stddensity Standard density
surftendown Downstream surface tension
surftenup Upstream surface tension
tailmach Tailpipe mach No.
tailnoise Tailpipe noise
tailpipe Tailpipe flag
tailrhov2 Tailpipe rho V2
tailvelliq Tailpipe liquid velocity
tailvelvap Tailpipe vapor velocity
tc Critical temperature
220 A File Format
Variable Name Variable Description
tempcalc Inlet temperature calculations
tempdown Downstream temperature
tempout Outlet temperature
tempspec Inlet temperature specification
tempup Upstream temperature
thermconddown Downstream thermal conductivity
thermcondup Upstream thermal conductivity
type Item type
usn Upstream node
valvecount Number of valves
valvetype Valve type
vapfrac Source vapor fraction
vc Critical volume
vchar Characteristic volume
veldown Downstream velocity
velup Upstream velocity
visca Viscosity A coefficient
viscb Viscosity B coefficient
viscdown Downstream viscosity
viscup Upstream viscosity
wall Wall thickness
walltemperature Wall temperature
watson Watson characterisation parameter
wind Wind velocity
zfactordown Downstream compressibility factor
zfactorup Upstream compressibility factor
B References 221
B References
1 “GPSA Engineering Data Book”.
2 “Chemical Engineering Volume 1”, J. M. Coulson and J. F. Richardson,Pergamon Press, 2nd Edition.
3 “Viscosity of Gases And Mixtures”, I. F. Golubev, National TechnicalInformation Services, TT7050022, 1959.
4 “Chemical Process Computations 1, Chemical Engineering-DataProcessing”, Raman, Raghu, Elsevier Applied Science Publishers Ltd, 1985.
5 “Journal Of Physics”, D. J. Berthalot, P.3 ,263.
6 “Technical Data Book-Petroleum Refining”, American Petroleum Institute,1977.
7 “A Computer Program for the Prediction of Viscosity and ThermalConductivity in Hydrocarbon Mixtures”, J.F. Ely and H.J.M. Hanley, NBSTechnical Note, 1039, 1983.
8 R.W. Hankinson and G.H. Thompson, AIChE Journal, 25, 653, 1979.
9 “A Study of Two-Phase Flow in Inclined Pipes”, H.D. Beggs and J.P. Brill, J.Petrol. Technol., P. 607, May, 1973.
10 “Gas Conditioning and Processing”, R. N. Maddox and L. L. Lilly, Volume 3,1982 by Campbell Petroleum Series, 2nd edition, 1990.
11 J. Orkiszewski, Journal of Petroleum Technology, B29-B38, June, 1967.
12 “Gas Conditioning and Processing”, R. N. Maddox and L. L. Lilly, Volume 3,1982 by Campbell Petroleum Series, 2nd edition, 1990.
13 API Technical Data Book Volume 1, American Petroleum Institute, 1983.
14 R.W. Hankinson and G.H. Thompson, A.I.Ch.E. Journal, 25, No. 4, P.6531979.
15 “The Properties of Gases &Liquids”, R.C. Reid, J.M. Prausnitz and B.E.Poling, McGraw-Hill, Inc., 1987.
16 “A Computer Program for the Prediction of Viscosity and ThermalConductivity in Hydrocarbon Mixtures”, J.F. Ely and H.J.M. Hanly, NBSTechnical Note 1039.
17 “Molecular Thermodynamics of Fluid Phase Equilibria”,J.M. Pausnitz, R.N.Lichtenthaler and E.G. Azevedo, 2nd Edition, McGraw-Hill, Inc. 1986.
18 C.H. Twu, IEC. Proc Des & Dev, 24, P. 1287, 1985.
19 “Viscosity of Crude-Oil Emulsions”, W. Woelfin, Spring Meeting, PacificCoast District, Division of Production, Los Angeles, Calif., Mar. 10, 1942.
20 W.R. Gambill, Chem Eng., March 9, 1959.
222 B References
21 “An Explicit Equation for Friction Factor in Pipe”, N.H. Chen, Ind. Eng.Chem. Fund., 18, 296, 1979.
22 “Sizing, Selection, and Installation of Pressure - Relieving Devices inRefineries”, API Recommended Practice 520, Part I, 6th Edition, AmericanPetroleum Institute, March, 1993.
23 “Guide for Pressure-Relieving and Depressuring Systems”, APIRecommended Practice 521, 3rd Edition, American Petroleum Institute,November, 1990.
24 “Easily Size Relief Devices and Piping for Two-Phase Flow”, J.C. Leung,Chem. Eng. Prog., P. 28, December, 1996.
25 “Internal Flow Systems”, D.M. Miller, 2nd Edition, BHR Group Limited,1990.
26 “Flow of Fluids Through Valves, Fittings and Pipe”, Crane Technical Paper410M. 1988.
27 “PIPE 3, Single and Two-Phase Pressure Drop Calculations in PipelineSystems”, HTFS Design Report 38, 1996.
28 “Les Pertes de Charges dans les Écoulements au Travers de”, A. Gardel,Bulletin Technique de la Suisse Romande, 83, 1957.
C Glossary of Terms 223
C Glossary of Terms
Adiabatic FlowAdiabatic flow is the constant enthalpy flow of a fluid in a pipe.
Choked FlowThe velocity of a fluid in a pipe of constant cross-sectional area cannot exceedthe sonic velocity of the fluid. If the flow of fluid in a pipe is great enough thatthe sonic velocity is reached, then a pressure discontinuity is seen at the exitend of the pipe.
Critical PressureThe critical pressure is the pressure at which the vapor density and liquiddensity of a substance may be the same.
Critical TemperatureThe critical temperature is the temperature at which the vapor density andliquid density of a substance may be the same.
DongleSee Security Device.
Equivalent LengthThe equivalent length of a pipe is the straight length of pipe which wouldcreate the same pressure drop as the actual pipe length plus losses due tobends and fittings.
224 C Glossary of Terms
Isothermal FlowIsothermal flow is the constant temperature flow of a fluid in a pipe. Ingeneral when the pressure of a gas reduces, there is a small change intemperature. This assumption leads to a small error in the calculated pressureprofile. In practice, for pipes of length at least 1000 diameters, this differencedoes not exceed 5% and in fact never exceeds 20%.
MABPThe Maximum Allowable Back Pressure on a relief device is the maximumpressure that can exist at the outlet of the device without affecting thecapacity of the device.
In general the MABP for a conventional pressure relief valve should notexceed 10% of the set pressure at 10% overpressure.
In general the MABP for a balanced pressure relief valve should not exceed40% of the set pressure at 10% overpressure.
Mach NumberMach number is the ratio of the fluid velocity to the sonic velocity in the fluid.
NodeNodes define the connection points between pipes, and pipes with sources.Each node must have a unique name.
Reduced PressureReduced pressure is the ratio of the absolute pressure to the critical pressureof the fluid.
Reduced TemperatureReduced temperature is the ratio of the absolute temperature to the criticaltemperature of the fluid.
ScenarioA scenario represents a set of flow and compositional data for all sources inthe system. It may also represent a particular set of limiting operatingconditions.
C Glossary of Terms 225
ScheduleThe schedule of a pipe defines a standard thickness for a given nominal pipesize. In general, flare and vent systems are constructed from schedule 40 or80 pipe.
Security DeviceThe hardware device that is connected to the parallel port of the computer.
SourceA source refers to a fluid entering the piping network regardless of the type ofpipe fitting from which it enters. the fluid is defined in terms of itscomposition, mass flowrate, pressure and temperature.
Static PressureThe pressure acting equally in all directions at a point in the fluid.
Physical properties are calculated at the static pressure condition.
TailpipeThe section of pipe between the discharge flange of the source valve and themain collection header is generally referred to as a tailpipe.
Total PressureThe sum of the static and velocity pressures.
Velocity Pressure
Given by2
ρU2
, also called the kinematic pressure.
226 Index
Index
A
Automation 115
B
binary interaction parameters 11
C
calculationssizing 104speed 103status 101stop 101type 101
Component Editor 6Component Manager 3components
binary interaction parameters 11changing 11combining 11estimating unknown properties 10list 4name string 5selecting 4selection filter 5type 4updating with user data 10
Connector 43Control Valve 71
D
dataadding/deleting 109filters 108printing 109protection 110tables 109
Database Editor
Index 227
component 112fittings 112pipe schedule 110
database featuresadding/deleting data 109grid controls 108
F
Flare Tip 95Flow Bleed 47
H
Horizontal Separator 50
M
modeling flare networksprimary objectives 102recommended sequence 102
N
Node Manager 41nodes
Connector 43Control Valve 71Flare Tip 95Flow Bleed 47Horizontal Separator 50Orifice Plate 56Relief Valve 81Tee 60Vertical Separator 65
Nodes 41noise 186
O
Orifice Plate 56
P
passwordsetting 110
physical properties 178Pipe Class Editor 39Pipe Manager 25pipes
multiple editing 38Pipe Class 39
pressure drop methods 157
228 Index
R
Relief Valve 81
S
Scenario Editor 17Scenario Manager 16scenario selector 16scenarios 15
adding single source 23adding/editing 17tools 23
sizingrecommended procedure 104
source tools 94adding single source scenarios 95updating downstream temperatures 95
sourcesControl Valve 71Relief Valve 81tools 94
Status bar 101
T
Tee 60
V
vapour-liquid equilibrium 175Vertical Separator 65VLE method 103