computational fluid dynamics i - udccaminos.udc.es/info/asignaturas/201/cfdi_sms_2.pdf · • sms...
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Universidad de A CoruñaEscuela Técnica Superior de Ingenieros de Caminos, Canales y Puertos
Computational Fluid Dynamics IPablo Rodríguez-Vellando Fernández-Carvajal
CFD IComputational Fluid Dynamics I
Hochschule Magdeburg-StendalFachbereich Wasser und Kreislaufwirtschaft
SMS
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• SMS (Surface-Water Modeling System) is a hydrodynamical calculus environment developed by• Brigham University
• U.S. Army Corps of Engineers
• Federal Highway Administration
• Including modules for
– Pre-process, for creating meshes for finite elements and finite volumes
– Post-process, for exporting, visualizing and rendering results
– Calculus, among which
• US Army Corps of Engineers
– TABS
» GFGEN, geometrical processing of the mesh
» RMA2, 2D model for sub-critic hydrodynamical calculus
» RMA4, water quality and transport of reactants
» RMA10, quasi-3D stratified flow for sub-critic hydrodynamical calculus
» SED2D-WES, for sediment transport
– ADCIRC, CGWAVE, for coastal analysis
– HIVEL2D, for super-critic flow
– HEC-RAS, one-dimensional calculus of channels
• FHA and others (FESWMS-FLO2DH, M2D, GHOST,…)
CFD IComputational Fluid Dynamics I
• There are other ‘families’ of hydrodynamical software such as Mike (Danish Hydraulic
Institute), Delft (Delft Hydraulics) or Fluent (Ansys),…
• We are going to focus on the 2D FEM hydrodynamical analysis and will be using mainly
RMA2 and RMA4
• The final aim will be obtaining the hydrodynamic fields for steady and unsteady
conditions, and further results also, such as the pollutants concentration or saline
intrusions. These data could be also used as inputs for other software codes.
• Teaching this friendly user tool within CFD I, completes aspects of hydraulics and
Computational Fluid Dynamics I, on theoretical aspects of hydrodynamical finite element
models which have been taught previously
• Also in the family• GMS Groundwater Modeling System
• WMS Watershed Modeling System
CFD IComputational Fluid Dynamics I
• RMA2 is a part of TABS (developed by the U.S. Army Corps of Engineers) that also includes
GFGEN, RMA4, RMA10 and SED2D-WES among others codes
• RMA2 models the sub-critic flow ( ) and includes tools for the wet-dry condition and porosity
trough marshy wet lands
• RMA2 is a FE model that solves the Shallow Water Equations taking an constant eddy viscosity and
assessing in that way the turbulent energy losses through a zero-equations turbulent model
• RMA4 is a FE model that, taking the hydrodynamics variables obtained at RMA2 as an input, gives the
concentration of a pollutant at the domain for unsteady conditions
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CFD IComputational Fluid Dynamics I
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• SMS is based upon the following modules
– The Mesh Module, for generating and managing 2D element meshes, to be used in connection with
RMA2, RMA4, SED-2D, HIVEL2D, ADCIRC, CGWAVE, FESWMS,…
– The Extruded mesh Module, with boundary adjusted cells, to be used in finite differences and in
connection with CH3D and ICM for hydrodynamical calculus
– The 2D and 3D Cartesian Grid Module, to be used in connection with finite differences modules with
cells parallel to the axis (STWAVE, GHOST y M2D, coastal and wave models)
– The Scatter Module, manages groups of scatter points for interpolating their characteristics (height) for
a given mesh
– The Map Module, for managing the earth information, takes into account four different types of objects:
• Features, to provide GIS characteristics (points (points, nodes or vertices), arcs and polygons, ordered in layers)
• Images, from maps, aerial views,… as TIFF, JPEG,…
• Drawings, providing additional information: text, lines, polygons,…
• DXF, AutoCad or Microstation files
– The 1-D Module, to be used in connection with HEC-RAS
CFD IComputational Fluid Dynamics I
• The access is done through
– Usuario: masteragua
– Contraseña: M4st3r4gu4
– Conectarse: AI
• The SMS screen is made up of
Menu bar
Edit window
Tool palette
Project Explorer
Graphic screen
Mode bar Status Bar
CFD IComputational Fluid Dynamics I
• The main modules we will be using are
Mesh module
Scatter module
Map module
• The Project Explorer Window allows to view all the data that makes up the project, is
used for switching modules, select coverages or data sets and set display settings
• Before starting we should stick to the International System for all measures by doing
Edit/ Current Coordinates
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
1. Creating a mesh introducing data trough the screen (Mesh mod)
In Mesh mode
We can create, edit and modify nodes
We can create, edit and modify ‘nodestrings’ connecting nodes
A 2D region is obtained
CFD IComputational Fluid Dynamics I
• Once we´ve got nodes and nodestrings we can distribute more nodes
– At the nodestrings editor we select all, and open the menuElements/Rectangular Patch
– In this dialog window we can distribute nodes and adjust the ‘bias’ to generate a quadrangular mesh
– Once created, we can select them with the elements editor
CFD IComputational Fluid Dynamics I
• At Elements/Merge Triangles we can join triangles into quadrilaterals
• At Elements/Split Quadrilaterals, quadrilaterals can be split apart
• At Elements/Linear<->Quadratic we can change the interpolation order of the elements
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Display options for shade, contours, vectors, information and plots
CFD IComputational Fluid Dynamics I
Pan, Zoom y Rotate, for displacing, zooming or rotating the view in 3D
Refresh, Frame, Display options and Plane view for applying changes,
adjusting the view to the mesh, show the whole of the display options or return to
the plan view
At Display/View, Plan, Front and Side views can be selected
CFD IComputational Fluid Dynamics I
• For avoiding duplicate nodes
Nodes/Delete Duplicate Nodes
• For renumbering nodes
– Select a nodestring and then Nodestring/Renumber
– A nodestring can be also defined clicking at the node and selecting CONTROL
– Band width modifications can be checked at info
• Save at File/Save Project
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• A feature point defines a position which is not in an arc to
force the creation of a node at that place. A feature node is
the same but on an arc, if they are not at the borders, they
are called feature vertices
• A feature arc is a sequence of segments which are grouped
together as a polyline, they can form polygons (with a given
area) or act as the borders of a river
• A feature polygon is defined inside one or more feature
arcs
point
arc
polygons
node vertex
At the maps module a mesh can be created from a .dxf, .shp or
directly trough a scanned map as .tif, .jpg, etc…
The elements to be managed are the feature objects (Arcs,
Nodes, Vertices and Polygons)
CFD IComputational Fluid Dynamics I
• At the Map Module the following icons are used to create and edit arcs,
nodes, vertices and polygons (feature objects), that can be managed in layers
• First of all we should do right click at the active coverage, to turn it into a 2D
mesh with Type/Models/TABS
Select node
Create node
Select vertex
Create vertex
Edit arc
Create arc (double click closes it)
Select arc group
Select a polygon (previously created from a close arc with
Feature Objects/Build Polygons)
CFD IComputational Fluid Dynamics I
• Polygons can be seen by switching on the Polygon fill option at the display icon
• Double clicking at the Polygon, we can adjust the number of vertices, materials,
the bias,…
• At Adaptative tesselation it splits the domain into triangles
• At Patch makes quadrilaterals (it requires 4 sides),…
CFD IComputational Fluid Dynamics I
• In Feature Objects/Map->2D Mesh creates the mesh and adds constant
heights if not specified
CFD IComputational Fluid Dynamics I
If saved, several files will be created:
*.sms Main file with the whole project
and several additional files that can come handy for pre and post process such as
*.bc Boundary conditions
*.geo Conectivities, geometry of nodes, materials
*_gf.run Executable gfgen
*_rm.run Executable RMA2
*.materials Materials
*.sim Simulations
*.map Map features
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
3. Giving heights to a mesh (Scatter mod)
• Scatter points can be created at the mesh module from a plain point by just
providing a certain height doing
Data/Mesh->Scatterpoint
they are therefore turned into a scatter stencil and can be saved at the scatter
module as a Scatter file (*.h5), that can co-exist with the rest of the files in the
project
• Scatter points can also be created directly at the at the scatter module. Once the
scatter file is done we can give heights to a mesh by doing
Scatter/Interpolate to mesh
and the heights of each of the points at the mesh are interpolated through the
scatter information
CFD IComputational Fluid Dynamics I
• Do not forget to tick the Map elevation at the dialog box
• From now on the mesh points have a certain height that can be mapped as a
contour map with several rendering options
Display Options/2D Mesh/Contours
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• If we are going to interpolate heights from a surveying *.dxf, we should activate the
bathymetry layers at the Project Explorer. The points can be turned into Scatter Points with
DXF->DXF Scatter point. Now we can do Scatter/Interpolate to mesh at the Scatter Module
• We can also import a surveying scatter type file and generate a mesh from it following the
isolines. At Data/Scatter Countour to Feature a contour line can be created at a certain
height that will be treated as a Feature arc to be used at the map module
CFD IComputational Fluid Dynamics I
• Once the feature arcs have been generated they can be turned into polygons and
the mesh can be generated in the same way as before. Do not forget to do
Type/Models/TABS clicking at the active coverage with the right hand button.
• Feature Objects/Build Polygons
• Feature Objects/Map to 2D mesh (do it twice if required)
• Heights can be given at Scatter/Interpolate to mesh (Map Z, on)
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
4. Boundary conditions, characterizing the mesh
• Once the mesh has been defined, boundary conditions can be assigned by
selecting the nodestring and doing RMA2/Assign boundary conditions
• Flowrate at the entrance (perpendicular to the boundary, 10m3/s) and depth at the
outlet (2m)
CFD IComputational Fluid Dynamics I
• Apart from flowrate and direction, an uneven distribution of the flow at the cross
section can be also specified
+ -+ +
• Boundary conditions are then loaded at the *.bc file
CFD IComputational Fluid Dynamics I
• At RMA2/Material Properties the
flow can be characterized by
choosing the eddy viscosity (E) and
the Manning coefficient (n)
• E will be taken as 1000 and n as
0.025 as default values
• At the SMS handbook the following
table is provided! Type of Problem E, lb-sec/ft2 E, Pascal-secHomogenous horizontal flow around an island 10-100 500-5000
Homogenous horizontal flow at a confluence 25-100 1100-5000
Steady-state flow for thermal discharge to a slow moving river 20-1000 1000-50000
Tidal flow in a marshy estuary 50-200 2500-10000
Slow flow through a shallow pond 0.2-1.0 10-50
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• Once the geometry, the boundary conditions, and the materials properties have
been introduced, a check can be done with
RMA2/Model Check
• Some of the most usual errors are the following
– The mesh has not been renumbered -> (Select Nodestrings/ Renumber)
– The elements are not quadratic ->(Elements/Linear<->Quadratic)
– The water depth specified is not big enough
– Provide WSE (at Model Control/Optional Bc control/ Initial WSE (given depth))
CFD IComputational Fluid Dynamics I
• For calculating the hydrodynamics we do RMA2/Run GFEN and this…
– Generates a binary file, *.bin with geometry to be able to run RMA2
– All the possible problems are listed at *.ot1
– The b.c. do not affect the generation of this
• Once the geometry has been ‘run’, we can do RMA2/Run RMA2
– Problems are listed at *.ot2
– The result file is written *.sol
CFD IComputational Fluid Dynamics I
• At RMA2/Model control the FE
code parameters can be changed
• At Files we can control
– Hotstart input file to introduce
initial data to be taken as initial
conditions
– Hotstart output file to obtain an
intermediate results outcome
• At Timing we can control the
unsteady output
• At Materials you can set a dry/wet
condition specify default manning,….
CFD IComputational Fluid Dynamics I
• Steady or Dynamic (unsteady) conditions can be chosen at RMA2/Model Control/Timing
• At Steady state depth convergence, the accepted error to achieve convergence
is set (for example 0.0001)
• At Iterations/Initial solutions the number of iterations for the only time step is set
(steady flow). When unsteady flow is chosen the computation time box is
activated
CFD IComputational Fluid Dynamics I
• Now we save and run with RMA2/Run RMA2 and hope for the best
• The GFGEN module is firstly run for compiling the geometry and if everything
goes fine we can go for Run RMA2 at the lower right corner of the window
CFD IComputational Fluid Dynamics I
• We have now all the information at the Project Explorer.
• At the Display Options Icon we can now choose if we want to display the vector
field or the contour field and we can specify the rendering options
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• At Display/2D Mesh/Contours we can choose
– Contour method (colour fill, normal linear,…)
– En Contour range and Contour intervals we can specify the range of colours for
the iso-lines
– We can tick/untick Legend for displaying the legend or not
– ….
CFD IComputational Fluid Dynamics I
• At the node editor el we can select a particular node and obtain information about the
velocity and depth at a certain point
CFD IComputational Fluid Dynamics I
• At the Display options/2D Mesh/Vectors we can adjust the parameters at the vector field
• At Color Range we can assign different colours to different velocity magnitudes,…
• If we change the boundary conditions, save and run RMA2 we will get a second solution
that can co-exist with the former at the Project Explorer
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• To obtain results from an unsteady
problem we should choose
Timing/Dynamic at the RMA2 Model
Control Dialog box
• At Iterations we can choose the
number of iterations and converge
parameters for depth at each time step
• At Computational Time we can
choose the number of steps and the
time for each one
CFD IComputational Fluid Dynamics I
• For obtaining results varying in time we should modify the boundary conditions at
RMA2/ Assign BC
• Once there, we can choose Transient and define the curve
• We could import there a file from an excel file (for example) or introduce new data with New
CFD IComputational Fluid Dynamics I
• Once RMA2 has been run a window appears at the left bottom corner showing
the results for each of the time steps
• The SMS post- processor also allows for a creating movies with Data/ Film Loop
CFD IComputational Fluid Dynamics I
• There we can prepare animations for scalar and vectorial fields and also flow trace movies
CFD IComputational Fluid Dynamics I
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• The RMA4 model is used for tracking a constituent concentration in 2D models,
through the resolution of the transport equation
• It should take the hydrodynamic results from a previous run of RMA2 as an input
• It should be used with metric units
CFD IComputational Fluid Dynamics I
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• First we should obtain the hydrodynamic fields for a certain domain
• Lets create a winding channel in metric units (Edit/Current Coordinates)
• At the Map module create some Feature Arcs (do not forget to right buttom
Type/Models/TABS at the coverage) and build a mesh (Feature Objects/Build Polygons)
• Feature Objects/Attributes, refine a bit and the create with Feature Objects/Maps >> 2D Mesh
CFD IComputational Fluid Dynamics I
• RMA2/Model Contol/Timing: Time step 0.1, number of time steps 240, maximum time 24h
• We will know create Nodestrings at the inlet and the outlet and introduce boundary conditions at
RMA2/Assigning boundary conditions (10m3/s at the inlet and from 5 to 2 m at the outlet twice
along the day)
• Default Eddy viscosity and Mannings will be kept
• Nodestrings Renumber, Save project, Run RMA2 (Sometimes it could show an error at GFGEN
which is not real, try to run first for steady state conditions)
CFD IComputational Fluid Dynamics I
• We will now introduce a concentration of a certain pollutant at the inlet on the steady solut.
• At RMA4/Model Control, the Start time will be set to 0, the Time step 0,1 hours, the Total steps to 240 and the max time to 24 (if smaller than time steps plus total steps, the solution will
be truncated)
• At files, choose *.sol and tick Write RMA4 Solutions File and Activate full report
• Last time step set to 24.0 and time subtracted 0
CFD IComputational Fluid Dynamics I
• RMA4/Assign boundary conditions/Constant, and introduce a constant concentration of
999ppm (the units of the solution will those of the input)
CFD IComputational Fluid Dynamics I
• At RMA4/Material Properties choose a diffusion coefficient of 10m2/s
• Save! All the affected files should be at the same directory!
• RMA4/Run RMA4
• Open RMA4 results with File/Open/*.qsl
• At Data/Film loop an animation can be done (for an hour, for example)
CFD IComputational Fluid Dynamics I
• Observation sections can be defined by right clicking at the project explorer Map Data/New Coverage/Observation
• At this coverage we can define a couple of arcs as cross sections
• Once done we can go to Display/Plot Wizard/Observation profile and plot the present data
• At Display/Plot Display options we can costumize, export the plot, etc
CFD IComputational Fluid Dynamics I
• Observation points can be also defined at the same coverage to plot variations in time of the flow
variables at that point
• Once created we can go to Display/Plot Wizard/Time series and plot the present data
• At Display/Plot Display options we can costumize, export the plot, etc
CFD IComputational Fluid Dynamics I
• We can compare computed values with real ones if we have them for depth, velocity,…
• If we double click on the observation arc or point or do Feature Objects/Attributtes, and
then we do Module/2D mesh, velocity mag (for example), we can introduce measured data
through the keyboard or also import data from a file, for arcs and points, at both steady and
unsteady (trans) conditions
CFD IComputational Fluid Dynamics I
• Once done we can go to Mesh Module/Display/Plot Wizard/Computed versus observed data and plot the present data
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
Tutorial 1.Obtaining the flow at a meander from a scanned picture. The St Mary meander
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• We are going to open an scanned .jpg image first
File/Open/c:/Program files/SMS10.0/Tutorials/General/Overview/data files/stmary.jpg
A
B
CFD IComputational Fluid Dynamics I
• This file is already georeferenced. When not, the
Resister Image dialog appears and relative and
absolute coordinates should be matched for three
points (1,2 and 3)
• Feature objects can be converted from an existing
.dxf or .dwg file or from the survey data
• Feature objects can also be digitalized inside SMS by
doing
• To create a feature arc, the icon is selected and the arc is adjusted to the topographic line of the boundary
– The last vertex can be removed with the ‘backspace’
– ESC will erase the whole arc. Double click to finish the arc
– At Feature Objects/Redistribute vertices, the number of vertices of an arc can be changed
– A new coverage could be imported to co-exist with the one we have just done by doing
File/Open/c:/Program files/SMS10.0/Tutorials/General/Overview/data files/stmary1.map
– Several coverages can co-exist at the same project and can be activated, deactivated, erased, renamed, etc.
– En Feature Objects/Vertices <->Nodes, nodes are swapped by vertices and vice-versa and therefore arcs
connect or split apart
– Vertices can also be created, moved and erased
– At Feature Objects/Transform, feature object
can be provided with a height
CFD IComputational Fluid Dynamics I
• Materials should be assigned by first creating them with
Edit/Materials data
• The types can be later defined at RMA2/Material properties
• To see the material we can go to Display/Maps/Polygon fill/Materials
CFD IComputational Fluid Dynamics I
• Polygons are going to be built inside closed arc
groups
• To define polygons we should first do right click on
the coverage, which should be turned into a 2D
mesh with Type/Models/TABS
• Once all the arcs have been generated we can build
the polygons with
Feature Objects/ Build Polygons
• Selecting the polygon with a double click (or in Feature Objects/Attributes) the mesh can be
characterized and modified by adding or removing
vertices, changing the triangulation method…
CFD IComputational Fluid Dynamics I
• Once the information about the ground has been introduced, and the mesh defined, it
should be created with Feature objects/Map to 2D mesh
• At the Mesh Mode check for duplicate nodes at Nodes/Delete duplicate nodes and
renumber at Nodestring/Renumber from a Nodestring
CFD IComputational Fluid Dynamics I
• Now we should add bathymetrymetric data. Open the file with the survey information
File/Open/c:/Program files/SMS10.0/Tutorials/General/Overview/data files/stmary_bathy.h5
• At the scatter mode select Scatter/Interpolate to mesh
• Select Map Z at the box. Now the z-coordinate has been incorporated to the mesh
CFD IComputational Fluid Dynamics I
• Now we can see the bathymetric contour field by clicking at the project
CFD IComputational Fluid Dynamics I
• Now for running the model we should introduce eddy viscosities and Manning coeficients
for every material we had previously defined
E(lb-sec/ft2) n(sec·ft -1/3)Left_Channel 50 0.04Main_Channel 50 0.03Right_Channel 50 0.04
CFD IComputational Fluid Dynamics I
• As boundary conditions we can set 40000 ft3/s (some 1500m3/s) at the inlet and
a 20ft water height (some 6m) at the outlet
• Afterwards
RMA2/Model Check
File Save Project
RMA2/Run RMA2
• If GFGEN doesn´t work renumber the mesh and try again
• At the project explorer we´ve got now the solution as a vector and a contour field
CFD IComputational Fluid Dynamics I
CFD IComputational Fluid Dynamics I
CFD IComputational Fluid Dynamics I
Tutorial 2. Meirama LakeObtaining the flow from GIS files *.shp, *.dxf, *.txt,…
CFD IComputational Fluid Dynamics I
Index
0. Introduction to SMS
1. Creating a mesh introducing data trough the screen (Mesh mod)
2. Creating a mesh from a .dxf, .shp, .jpeg (Map mod)
3. Giving heights to a mesh (Scatter mod)
4. Boundary conditions, characterizing the mesh
5. Execute RMA2
6. Rendering the results
7. Unsteady flow
8. Execute RMA4
9. Tutorial 1. St Mary meander
10. Tutorial 2. Meirama Lake
CFD IComputational Fluid Dynamics I
• We should now switch to international coordinates at Edit/Current Coordinates
• In order to introduce real data for hydrodynamic characterization of flows it is very useful to
consider compatibility with other GIS and CAD programs, such as ArcGIS, AutoCAD etc… SMS
can read data from *.dxf, *.shp, *.txt file, etc… If we start with a file containing surveying data
(SIGPAC) we can also proceed as follows File/Open/Barcés.txt/Open file as XYZFiles(*.xyz)
• It takes the data as a scatter file and we can save it as a *.h5 and a *.sms file
CFD IComputational Fluid Dynamics I
• Let´s do now at the Scatter module Data/Scatter Contour to feature, at heights 180, 150
and 80 m, with a spacing of 30m
CFD IComputational Fluid Dynamics I
• Lets close the ‘dam’ at height 180 m at the Maps Module and erase the non-required arcs
• Lets hide the scatter points
CFD IComputational Fluid Dynamics I
• Following, materials can be defined in the Mesh Module at Edit/Materials Data, where three
new materials are created
CFD IComputational Fluid Dynamics I
• Right button click at the coverage, then Type/model/TABS
• Feature Objects/Build Polygons
• Select Polygons, then double click at polygon and define the mesh with a smaller
refinement
• Assign the three materials and show them with the display options
CFD IComputational Fluid Dynamics I
• Once we are done, Feature Objects/Map->2D Mesh
• Do it twice, if necessary
CFD IComputational Fluid Dynamics I
• Heights can be provided with Scatter/Interpolate to mesh (Do not forget to tick Map Z)
• Now heights can be seen as a contour map through the display options
CFD IComputational Fluid Dynamics I
• Following, materials can be defined in the Mesh Module at RMA2/Material Properties
• We are going to generate three different types of materials with Mannings, n=0.03, 0.025 y
0.02 (s·m-1/3) (given as default as 0.025) and Eddy Viscosity, E=2000 Pascals·s
• The RMA2 is very sensible to E. It should be adjusted with care and calibrated when possible.
The values proposed by the handbook are the following
CFD IComputational Fluid Dynamics I
Type of Problem E, lb-sec/ft2 E, Pascal-secHomogenous horizontal flow around an island 10-100 500-5000
Homogenous horizontal flow at a confluence 25-100 1100-5000
Steady-state flow for thermal discharge to a slow moving river 20-1000 1000-50000
Tidal flow in a marshy estuary 50-200 2500-10000
Slow flow through a shallow pond 0.2-1.0 10-50
• Before running RMA2 we should renumber the mesh selecting a nodestring and doing
Nodestrings/Renumber
• Introduce b.c.: 181m at the dam spillway (change height of the spillway to 180m). An
inflow at the NW nodestring of some 100 m3/s and spot inflow velocity of (1,1) m/s at 45º at
a certain SW point by doing (RMA2/Assign BC/Velocity components)
CFD IComputational Fluid Dynamics I
• The model can be now run with
– RMA2/Model Check/Run check
– Run RMA2
– Run RMA2
CFD IComputational Fluid Dynamics I
CFD IComputational Fluid Dynamics I