fluent 15.0 beta features manual

Fluent 15.0 Beta Features Manual

Release 15.0ANSYS, Inc.

February 2014Southpointe

275 Technology Drive ANSYS, Inc. iscertified to ISO

9001:2008.Canonsburg, PA 15317

[email protected]

http://www.ansys.com

(T) 724-746-3304

(F) 724-514-9494

1Release 15.0 - SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

of ANSYS, Inc. and its subsidiaries and affiliates.

Copyright and Trademark Information

2014 SAS IP, Inc. All rights reserved. Unauthorized use, distribution or duplication is prohibited.

ANSYS, ANSYS Workbench, Ansoft, AUTODYN, EKM, Engineering Knowledge Manager, CFX, FLUENT, HFSS, AIM

and any and all ANSYS, Inc. brand, product, service and feature names, logos and slogans are registered trademarks

or trademarks of ANSYS, Inc. or its subsidiaries in the United States or other countries. ICEM CFD is a trademark

used by ANSYS, Inc. under license. CFX is a trademark of Sony Corporation in Japan. All other brand, product,

service and feature names or trademarks are the property of their respective owners.

Disclaimer Notice

THIS ANSYS SOFTWARE PRODUCT AND PROGRAM DOCUMENTATION INCLUDE TRADE SECRETS AND ARE CONFID-

ENTIAL AND PROPRIETARY PRODUCTS OF ANSYS, INC., ITS SUBSIDIARIES, OR LICENSORS. The software products

and documentation are furnished by ANSYS, Inc., its subsidiaries, or affiliates under a software license agreement

that contains provisions concerning non-disclosure, copying, length and nature of use, compliance with exporting

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ANSYS, Inc. is certified to ISO 9001:2008.

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For U.S. Government users, except as specifically granted by the ANSYS, Inc. software license agreement, the use,

duplication, or disclosure by the United States Government is subject to restrictions stated in the ANSYS, Inc.

software license agreement and FAR 12.212 (for non-DOD licenses).

Third-Party Software

See the legal information in the product help files for the complete Legal Notice for ANSYS proprietary software

and third-party software. If you are unable to access the Legal Notice, please contact ANSYS, Inc.

Published in the U.S.A.

Release 15.0 - SAS IP, Inc. All rights reserved. - Contains proprietary and confidential informationof ANSYS, Inc. and its subsidiaries and affiliates.2

Beta Features Manual

Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1. New Beta Features in Fluent 15.0 .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2. Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52.1. Fluid-Structure Interaction (FSI) ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.2. Multi-Grid Parallel FieldView Export ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3. Meshes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73.1. Smoothing Registers ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3.2. Meshing Mode Access .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4. Boundary Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94.1. Reference Temperature from a Boundary .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4.2. Impedance Boundary Conditions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.2.1. Overview .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.2.2. Restrictions and Limitations .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

4.2.3. Theory .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

4.2.4. Using Impedance Boundary Condition .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.3. Wave Spectrum for Random Wave Boundaries .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

4.4. Average Pressure Specification For Radial Profiles ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

5. Physical Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155.1. Using REFPROP v9.1 Database in the NIST Real Gas Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5.1.1. Legal Notice .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5.1.2. Changing the Version of the REFPROP Database .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5.1.3. Additional Features Supported by the REFPROP v9.1 Database .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

5.1.4. Limitations on Using the REFPROP v9.1 Database .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

6. Heat Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176.1. Enhanced Encapsulation for Shell Conduction and the S2S Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

7. Heat Exchangers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197.1. Improved Curve Fitting for Heat-Exchanger Model .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

7.1.1. Limitations ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

7.1.2. Usage ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

7.2. Alternate Formulation for the Dual Cell Heat Exchanger ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

8. Turbulence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218.1. Explicit Algebraic Reynolds Stress Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

8.1.1. Accessing the WJ-BSL-EARSM Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

8.1.2. Applying Scale-Adaptive Simlulation (SAS) with WJ-BSL-EARSM ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

8.1.3. References .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

8.2. Near-Wall Treatment for the Porous Media Interface .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

8.2.1. Accessing the Turbulent Wall Treatment Option .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

8.2.2. Example .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

8.3. Near-Wall Treatment for Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

8.3.1. Theory .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

8.3.1.1. Momentum Equations .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

8.3.1.2. k- Turbulence Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

8.3.1.3. Iteration Improvements .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

8.3.2. User Interface .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

8.3.3. Example .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

8.3.4. References .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.4. Buoyancy Effects on Omega-Based Turbulence Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.4.1. Theory .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

8.4.2. User Interface .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

9. Combustion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

iiiRelease 15.0 - SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information


9.1. Char Burnout Kinetics (CBK) Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

9.1.1. References .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

9.2. Modeling Electrochemistry .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

9.2.1. Theory .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

9.2.2. Using Electrochemical Reactions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

9.2.2.1. Limitations .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

9.2.2.2. Setting Electrochemical Reactions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

10. Pollutants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5310.1. Coal Derived Soot ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

10.1.1. Using the Coal Derived Soot Model .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

10.1.1.1. References ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.2. Atomic Balance for Sulfur .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.3. Mercury Pollutant Formation .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.3.1. Mercury Speciation in Coal Flames .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.3.1.1. Overview .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

10.3.1.2. Governing Equations for Mercury Transport ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

10.3.1.3. Mercury Speciation Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

10.3.1.3.1. One Step Mechanism ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

10.3.1.3.2. Two Step Mechanism ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

10.3.1.3.3. Detailed (Wilcox) Mechanism ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

10.3.1.4. Species Production Sources from Different Fuel Types .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

10.3.1.4.1. Hg and HCl Production in a Gaseous Fuel ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

10.3.1.4.2. Hg and HCl Production in a Liquid Fuel ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

10.3.1.4.3. Hg and HCl Production from Coal ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

10.3.1.4.4. Hg and HCl from Char .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

10.3.1.4.5. Hg and HCl from Volatiles ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

10.3.1.5. Species Production/Consumption due to Elementary Reactions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

10.3.1.6. Mercury Species Capture and Retention in Ash Residue .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

10.3.1.7. Mercury Species Capture using Sorbent Injection .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

10.3.1.8. Mercury Formation in Turbulent Flows .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

10.3.1.8.1.The Turbulence-Chemistry Interaction Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

10.3.1.8.2. The PDF Approach .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

10.3.1.8.3. The Mean Reaction Rate .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

10.3.1.8.4. The PDF Options .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

10.3.2. Using the Mercury Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

10.3.2.1. Setting Up the One Step Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

10.3.2.2. Setting Up the Two Step Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

10.3.2.3. Setting Up the Detailed (Wilcox) Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

10.3.2.4. Defining the Fuel Streams .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

10.3.2.5. Defining the Mercury Fuel Stream Settings .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

10.3.2.6. Setting Mercury Parameters for Gaseous and Liquid Fuel Types .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

10.3.2.7. Setting Mercury Parameters for a Solid Fuel ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

10.3.2.8. Setting Turbulence Parameters ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

10.3.2.9. Specifying a User-Defined Function for the Hg Rate .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

10.3.2.10. Defining Boundary Conditions for the Mercury Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

10.3.3. Solution Strategies .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

10.3.4. Postprocessing .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

10.3.5. DEFINE_HG_RATE UDF Macro .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8010.3.5.1. Description .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

10.3.5.2. Usage .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

10.3.5.3. Example 1 .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

10.3.5.4. Hooking DEFINE_HG_RATE UDFs .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Release 15.0 - SAS IP, Inc. All rights reserved. - Contains proprietary and confidential informationof ANSYS, Inc. and its subsidiaries and affiliates.iv


10.3.5.5. Hg Macros .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

10.3.6. Mercury Model Dialog Box A Quick Reference Guide .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

10.3.7. References ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

11. Acoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9311.1. Modal Analysis .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

11.1.1. Limitations ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

11.1.2. Modal Analysis Theory ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

11.1.3. Using the Modal Analysis Model .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

11.1.4. Setting Model Parameters ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

11.1.5. Postprocessing of the Modal Analysis Model .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

11.1.5.1. References ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

11.2. Band Analysis of Acoustic Sources .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

12. Discrete Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9912.1. Extended Collision Stencil .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

12.2. Tracking of Child Droplets Within the Same Time Step .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

12.3. Linearized Source Terms .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

12.4. Volume Injections .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

12.4.1. Limitations .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

12.4.2. Using the Volume Injection .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101

12.5. Discrete Element Method with Periodic Boundary Conditions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

13. Multiphase Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10513.1. Interphase Species Mass Transfer ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

13.1.1. Overview .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

13.1.2. Theory .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

13.1.2.1. Modeling Approach .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

13.1.2.1.1. Equilibrium Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

13.1.2.1.2. Two-Resistance Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

13.1.2.2. Species Mass Transfer Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

13.1.2.2.1. Raoults Law .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

13.1.2.2.2. Henrys Law .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

13.1.2.2.3. Equilibrium Ratio .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

13.1.2.3. Mass Transfer Coefficient Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

13.1.2.3.1. Constant .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

13.1.2.3.2. Sherwood Number .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

13.1.2.3.3. Ranz-Marshall Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

13.1.2.3.4. Hughmark Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

13.1.2.3.5. User-Defined .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

13.1.3. Using the Species Mass Transfer Models ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

13.2. Implicit Virtual Mass Force .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

13.3. Wave Spectrum for Random Wave Open Channel Boundaries .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

13.3.1. Definitions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

13.3.2. Wave Spectrum Implementation Theory .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

13.3.2.1. Long-Crested Random Waves (Unidirectional) ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

13.3.2.1.1. Pierson-Moskowitz Spectrum ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

13.3.2.1.2. Jonswap Spectrum ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

13.3.2.1.3. TMA Spectrum ..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

13.3.2.2. Short-Crested Random Waves (Multi-Directional) ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

13.3.2.2.1. Cosine-2s Power Function (Frequency Independent) ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

13.3.2.2.2. Hyperbolic Function (Frequency Dependent) ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

13.3.2.3. Superposition of Individual Wave Components Using the Wave Spectrum ..... . . . . . . . . . . . . . . 120

13.3.3. Using the Wave Spectrum Boundary Condition .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

13.3.4. Reporting During Initialization and Wave Spectrum Analysis ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

vRelease 15.0 - SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information



14. Solver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12514.1. Recursive Projection Method ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

14.2. Reduced Rank Extrapolation (RRE) Method .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

14.2.1. References .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

14.3. Executing Commands at a User-specified Iteration or Time Step .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

14.3.1. Executing a Command at a Particular Iteration .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

14.3.2. Executing a Command at a Particular Time Step .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

14.4. Alternative Rhie-Chow Flux With Moving Or Dynamic Meshes .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

14.5. Automatic Solver Defaults Based on Setup .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

15. Custom Field Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13315.1. Postprocessing Unsteady Statistics ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

16. Turbomachinery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13516.1. Pitch-Scale Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

16.2. Implicit Mixing-Plane Model ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

17. Parallel Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13917.1. Laplace Partitioning .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

18. Fluent in Workbench . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14118.1. Performing Transient Two-Way Simulations with Fluent and ANSOFT .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

18.2. Working with Custom Input Parameters ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

18.3. Using UDFs to Compute Output Parameters ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

18.4. Creating Output Parameters for Surface/Volume Monitors ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

19. User-Defined Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14519.1. Six-DOF Motion Constraint Using UDFs ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

20. Fluent as a Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14720.1. ANSYS Session Manager .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

20.1.1. Using ANSYS Session Manager .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

20.1.2. Configuring ANSYS Session Manager .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

20.2. Fluent Remote Console .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

20.2.1. Connecting to ANSYS Session Manager .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148

20.2.2. Concurrent Access .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

20.2.3. Interactive Prompts for Text Commands .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

20.3. Fluent as a Server SDK .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

20.3.1. IAnsysSessionManager CORBA Interface .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

20.3.2. COM Connectors ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152

20.3.2.1. Interfaces .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152

20.3.2.2. Registering the COM Connectors ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

20.3.3. Interactive Text User Interface Prompts .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

20.3.3.1. Using Interactive Prompting .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156

20.3.3.2. Exceptions .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

20.3.3.3. Example Code Listing .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

21. Population Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15921.1. Coulaloglou and Tavlarides Breakage ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

21.1.1. References ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

22. Adjoint Module Add-On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16122.1. Multiple Objective Design .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

22.1.1. Overview .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

22.1.2. Using the Multiple Objective Design Tool ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162

22.2. Prescribed Displacements .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

22.2.1. Overview .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

22.2.2. Usage .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

Release 15.0 - SAS IP, Inc. All rights reserved. - Contains proprietary and confidential informationof ANSYS, Inc. and its subsidiaries and affiliates.vi


Chapter 1: Introduction

This document contains information about ANSYS Fluent 15.0 beta features, which provide options for

modeling and reporting that are outside of the normal scope of ANSYS Fluent. These features are not

always accessible through the standard menus and dialog boxes, and will require the following text

user interface (TUI) command to enable them:

define beta-feature-access

Note

Please note that if you enable beta features in this case, use any beta features, and then

disable beta features, the beta features you put into use may still be active, even though

the text and graphical interfaces for these features may no longer be visible. It is

therefore recommended that you save a separate copy of the case before any beta

feature is activated. This will allow you to return to working on the case with only released

features if you desire.

Important

Note that beta features have not been fully tested and validated. ANSYS, Inc. makes no

commitment to resolve defects reported against these prototype features. However,

your feedback will help us improve the overall quality of the product.

Note

Beta features are not subject to our Class 3 error reporting system. In addition, we will not

guarantee that the input files using this beta feature will run successfully when the feature

is finally released so you may, therefore, need to modify the input files.

1.1. New Beta Features in Fluent 15.0

The following beta features are new in Fluent R15:

Numerics

Automatic adjustment of various solver settings based on the class of problem being solved and the

models in use. (Automatic Solver Defaults Based on Setup (p. 130))

Average pressure specification is made available with radial profiles and with the Radial EquilibriumPressure Distribution option. (Average Pressure Specification For Radial Profiles (p. 14))

Wave spectrum modeling for random wave boundary conditions when using the VOF model with open

channel boundaries. (Wave Spectrum for Random Wave Open Channel Boundaries (p. 116))



An improved formulation of the Rhie-Chow flux treatment for unsteady terms. (Alternative Rhie-Chow

Flux With Moving Or Dynamic Meshes (p. 130))

Impedance boundary condition option for Mass Flow and Velocity boundaries. (Impedance Boundary

Conditions (p. 10))

Solver-Meshing

Ability to smooth wrinkled surfaces between marked and unmarked regions. (Smoothing Registers (p. 7))

Parallel

A Laplace partitioning option that extends the Laplace coarsening method to ensure that partition in-

terfaces do not lie along areas of high cell aspect ratio. This improves convergence in parallel for highly

stretched cells (for instance, in some dynamic mesh applications). (Laplace Partitioning (p. 139))

Performance improvement for FieldView exports.

Turbulence

Enhancements to the existing band analysis for acoustic sources beta feature. (Band Analysis of Acoustic

Sources (p. 96))

Improvements to the formulation for the Menter-Lechner near-wall treatment (available for standard,

realizable, and RNG k- turbulence models). (Near-Wall Treatment for Models (p. 29))

Multiphase

Generalized species mass transfer model. (Interphase Species Mass Transfer (p. 105))

Implicit virtual mass treatment for improved convergence in steady-state multiphase simulations. (Im-

plicit Virtual Mass Force (p. 116))

Discrete Phase

Volume injection type. (Volume Injections (p. 101))

DEM model compatibility with periodic boundary conditions. (Discrete Element Method with Periodic

Boundary Conditions (p. 103))

Reacting Flow

Generalized electro-chemistry model. (Modeling Electrochemistry (p. 44))

Support for NIST database version 9.1 (separately installed). (Using REFPROP v9.1 Database in the NIST

Real Gas Models (p. 15))

Adjoint

Multi-objective optimization tool that determines optimal mesh morphing to maximize an objective

function based on sensitivity data from an arbitrary set of observables and/or flow conditions. (Multiple

Objective Design (p. 161))

Prescribed design changes tool that allows you to evaluate the effect of a user-specified boundary

shape change on the chosen observable. (Prescribed Displacements (p. 166))


Introduction

Fluent as a Server

Support for interactive prompting for text commands arguments. (Interactive Prompts for Text Com-

mands (p. 150))

Fluent in Workbench

Data interpolation is performed if the available initial data file is not compatible with the current

mesh/case file.

EM mapping for fluid cell zones.

Ability to define output parameters for surface/volume monitors.

Ability to make multiple upstream mesh connections to the Fluent Setup cell.

Included in the information about the beta features are references to related chapters and sections in

the ANSYS Fluent 15.0 Getting Started Guide, Users Guide, Theory Guide, UDF Manual, Fuel Cell Modules

Manual, and Population Balance Module Manual.



New Beta Features in Fluent 15.0

Chapter 2: Files

2.1. Fluid-Structure Interaction (FSI)

When setting up a fluid-structure interaction problem, you can ensure that the forces mapped to the

FEA mesh are conserved by performing the following steps:

1. Enable the beta feature access (as described in Introduction (p. 1)).

2. Read an FEA mesh, using either the Read button of the Volume FSI Mapping or Surface FSI Mappingdialog box, or the file/fsi/read-fsi-mesh text command.

3. Enable the conservation of the mapped forces by using the following text command:

file fsi conserve-force?

2.2. Multi-Grid Parallel FieldView Export

In parallel simulations with beta features enabled, three additional TUI commands are available for ex-

porting FieldView files. These make use of parallel optimizations giving improved performance. These

commands are:

/file/export/fieldview-unstruct-parallel-grid/file/export/fieldview-unstruct-parallel-result/file/export/fieldview-unstruct-parallel-combined

Usage of these commands is the same as for their non-optimized counterparts. When using the parallel-

optimized commands, each partition writes out a grid for each cell zone that is exported. A regions file

is also written that contains information about which grids are part of the same cell zone.

Important

FieldView does not support more than 10,000 grids



Chapter 3: Meshes

3.1. Smoothing Registers

If the surface between a marked and an unmarked region is wrinkled, you can use the /adapt/smooth-register TUI command to smooth it.

> /adapt/smooth-registermarking register id/name [] 0

118586 cells marked after smoothing step 1 119718 cells marked after smoothing step 2

The smoothing is accomplished by marking additional cells at the boundaries of the specified marked

register. The resulting collection of cells (i.e. the cells in the original register and the newly marked cells)

are added to a new register. The original register is preserved. You can thus see which cells have been

added to the marked region using register operations.

3.2. Meshing Mode Access

For 3D serial processing, you have the ability to switch from the solution mode of Fluent to the meshing

mode at any point, even when a mesh or case file is in memory. By enabling beta feature access (Intro-

duction (p. 1)), the following text command will always be available in the console, and can be used

as described in Switching Between Meshing and Solution Modes in the Getting Started Guide :

switch-to-meshing-mode



Chapter 4: Boundary Conditions

In this chapter you will find descriptions of beta functionality for setting up boundary conditions.

4.1. Reference Temperature from a Boundary

4.2. Impedance Boundary Conditions

4.3.Wave Spectrum for Random Wave Boundaries

4.4. Average Pressure Specification For Radial Profiles

4.1. Reference Temperature from a Boundary

When any fluid material inside the domain is an incompressible-ideal-gas or ideal-gas, the option ofspecifying the Density Method will appear as a drop-down list in the Operating Conditions dialogbox. Select one of the inlet boundaries (velocity inlet, mass-flow-inlet, pressure-inlet) for the calculation

of the operating density. The temperature specified in the temperature tab of an inlet boundary dialog

box will be used to calculate the operating density. If no boundary type is an Inlet, then ANSYS Fluent willcalculate the reference density using the default method.

Important

This option can be used only when you specify the temperature and/or species concentra-

tion on the boundary as constant.

This option will not be available if the boundary has a profile or UDF for temperature.

This option is only available for the pressure-based solver.

Specifying the inlet boundary for the calculation of reference density helps in predicting quiescent

flows.



Figure 4.1: The Operating Conditions Dialog Box

After enabling beta feature access (Introduction (p. 1)), you can use the following text command:

define operating-conditions use-inlet-temperature-for-operating-density

Enter the Zone-id/name [()].

4.2. Impedance Boundary Conditions

Impedance boundary conditions contains the following sections:

4.2.1. Overview

4.2.2. Restrictions and Limitations

4.2.3.Theory

4.2.4. Using Impedance Boundary Condition

4.2.1. Overview

Traditional flow boundary conditions are reflective. The non-reflective boundary condition is fully non-

reflective. The impedance boundary condition (IBC) lies in between and provides the ability to specify

a partial reflection in the range from full-reflection to no-reflection. Impedance is a complex value; It is

the reflection that changes the amplitude and the phase of the incoming wave. The use of impedance

boundary conditions comes in cases where the flow in the simulation is highly influenced by reflected

waves from objects outside the computational domain. In such cases the acoustic wave interaction

from the larger domain can be modeled in the smaller domain through the use of impedance boundary

conditions.


Boundary Conditions

4.2.2. Restrictions and Limitations

The impedance boundary condition is available only in the pressure-based solver. It is incompatible

with steady-state flow, multiphase, or compressible liquid models (compressible-liquid method fordensity).

4.2.3. Theory

Impedance specifies an acoustic resistance in the frequency domain. It is a characteristic of the properties

of the media and specific geometry described by a ratio of the pressure perturbation to the normal

velocity perturbation at the boundary Blackstock [[1] (p. 14)].

(4.1)

=

where apostrophe denotes acoustic perturbation and hat denotes quantity in the frequency domain.

Fluent is a time domain solver. It cannot use the impedance from the frequency domain directly. The

above expression and all its variables have to be converted to the time domain. After the conversion

the relation between pressure and normal velocity perturbations is expressed through a convolution

integral.

(4.2) =

If impedance, , is unbounded in the time domain, then admittance is used (admittance is the

inverse of impedance). Fluent uses the reflection coefficient instead of impedance/admittance, to uni-

formly treat unbounded cases Fung [[2] (p. 14)]. The reflection coefficient is a ratio between reflected

and incoming wave amplitudes at the boundary. It is expressed through the impedance as:

(4.3)

=

+

Using a reflection coefficient, the relation between pressure and normal velocity perturbation is:

(4.4) = +

The discretized form of this expression is used in Fluent to connect acoustic pressure and normal velocity.

The computed acoustic perturbations are superimposed onto the pressure and velocity from non-re-

flecting boundary condition equations. The non-reflecting boundary condition equations provide mean

flow values at the boundary, which drive the flow in the domain.

The data for the reflection coefficient are available in the frequency domain. As such they usually do

not satisfy the causality and reality conditions. Fluent asks you to provide the reflection coefficient data

in the form of a special approximation. This approximation is based on the system theory which ensures

that the reflection coefficient in the time domain will satisfy the above conditions Fung [[3] (p. 14)].

The reflection coefficient is represented as a sum of zero, first and second order systems. The zero system

is described with a real value, the first order system is described with a real pole, and the second order

system is described with a pair of complex conjugate poles. Introducing a system variable, = the

complete approximation for the reflection coefficient is:



Impedance Boundary Conditions

(4.5) = +

++

+

+ +

+ +

= =

where is a real term,

is a number of real poles,

and

are real pole and its amplitude,

is a

number of complex conjugate pole pairs,

,

are real and imaginary part of the complex conjugate

pole,

and

are real and imaginary part of the amplitude of the complex pole.

To obey the causality and reality conditions, real pole !"

, real #$

and imaginary part %&

of the complex

conjugate pole should be positive. The passivity condition requires that the absolute value of zero order

term ' be less than 1. The above restrictions are enforced in the user interface. In addition you should

ensure that the absolute value of the reflection coefficient computed by this formula is less than 1.

The impedance data can be obtained from measurements or from an acoustic solver. Running these

data through a mathematics package will provide an approximation in terms of first and second order

poles.

4.2.4. Using Impedance Boundary Condition

The impedance boundary condition (IBC) is available for use in the Pressure Inlet, Pressure Outlet,Velocity Inlet and Mass Flow Inlet dialog boxes. The example below shows you how to activate theIBC for a Pressure Outlet case. Similarly, you can activate IBC for Pressure Inlet, Velocity Inlet andMass Flow Inlet cases for compressible flows with the pressure-based solver.

1. Select pressure-outlet from the Boundary Condition task page and click the Edit... button.

2. In the Pressure Outlet dialog box, enable Impedance Boundary option.

The dialog box with expand to reveal Impedance Input.

3. In Impedance Input enter data for the reflection coefficient according to the approximation formula(Equation 4.5 (p. 12)).

Important

If flow is tangential to the boundary, then specify either From Neighboring Cell orDirection Vector for Back flow Direction Specification Method. Do not select Normalto the boundary because this computes the face velocity components from flux to zerovalues during initialization, which impairs solver convergence.


Boundary Conditions

The IBC is implemented on top of the non-reflective boundary condition. Choose a time step that

will not make the CFL number exceed a value of 1 in the cells adjacent to the impedance boundary.

Note

The mean flow in the domain should be well established before enabling IBC.



Impedance Boundary Conditions

4.3. Wave Spectrum for Random Wave Boundaries

For VOF simulations with open channel boundaries you can specify a wave spectrum to simulate random

wave boundary conditions. For details about this functionality refer to Wave Spectrum for Random

Wave Open Channel Boundaries (p. 116).

4.4. Average Pressure Specification For Radial Profiles

As a beta feature, the Average Pressure Specification option is also available with the following optionsat pressure outlet boundaries:

Radial Equilibrium Pressure Distribution

a profile for Gauge Pressure with profile type Radial

Bibliography[1] Blackstock, D.T.. Fundamentals of Physical Acoustics. John Wiley & Sons. 2000.

[2] Fung, K. -Y, Ju, H. and Tallapragada, B.. "Impedance and Its Time-Domain Extensions. AIAA Journal,

Vol. 38, No. 1 pp. 3038.. January 2000.

[3] Fung, K. -Y, Hongbin, Ju,. "Broadband Time-Domain Impedance Models. AIAA Journal, Vol. 39, No. 8.

January 2001.


Boundary Conditions

Chapter 5: Physical Properties

5.1. Using REFPROP v9.1 Database in the NIST Real Gas Models

By default, ANSYS Fluent uses the REFPROP v7.0 property database, which is dynamically loaded as a

shared library when you activate one of the NIST real gas models.

You have the option to use version 9.1 of the REFPROP database that is available on the Customer

Portal.

5.1.1. Legal Notice

NIST Standard Reference Data (SRD); 2013 by the U.S. Secretary of Commerce on behalf of the United

States of America. All rights reserved.

NO EXPRESS OR IMPLIED WARRANTY AS TO ANY MATTER, INCLUDING NO WARRANTY OF MERCHANT-

ABIILTY AND NO WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE. THE REFPROP DATABASE IS EX-

PESSLY MADE AVAILABLE ON AN AS IS BASIS.

5.1.2. Changing the Version of the REFPROP Database

Follow these steps to upgrade to the REFPROP v9.1 database.

1. On the Customer Portal, under Downoads Tools, locate the REFPROP v9.1 database.

2. Download the zip file containing the REFPROP v9.1 library and fluid files to your local system.

3. Unzip the zip file you have downloaded to the same directory as your case file.

4. In the ANSYS Fluent console, change the REFPROP library version by entering the following text command:

/define/user-defined/real-gas-models/nist-settings

5. When prompted with Upgrade refprop library version and fluids files? [no], answeryes.

6. Accept the default names for the refprop library and fluid files paths when prompted:

Select refprop library path ["refprop9.1"]

Select refprop fluid files path ["refprop9.1/lib"]

ANSYS Fluent will open REFPROP v9.1 library and report this information in the console:

Opening library "refprop9.1"...

Library "refprop9.1/lnamd64/librealgas.so" opened



To revert to the default REFPROP v7.0 property database, enter the /define/user-defined/real-gas-models/nist-settings command again and enter no at the prompt. ANSYS Fluent will reportthe change in the console window.

5.1.3. Additional Features Supported by the REFPROP v9.1 Database

The REFPROP v9.1 database includes the following additional fluids that are available for your analysis.

Pure fluids

d5.fldd4.fldcyclopen.fldc1cc6.fldcf3i.fldc3cc6.fld

ioctane.fldhcl.fldebenzene.flddmc.flddee.fldd6.fld

mlinolen.fldmlinolea.fldmdm.fldmd4m.fldmd3m.fldmd2m.fld

novec649.fldmxylene.fldmstearat.fldmpalmita.fldmoleate.fldmm.fld

r1233zd.fldr1216.fldr161.fldpxylene.fldoxylene.fldorthohyd.fld

re347mcc.fldre245fa2.fldre245cb2.fldr1234ze.fldre143a.fldr1234yf.fld

r40.fld

Pseudofluids

r507a.ppfr410a.ppfr407c.ppfr404a.ppfair.ppf

The following fluids are now allowed in mixtures:

water, heavy water, helium, hydrogen, parahydrogen, deuterium, neon, ammonia, fluorine, methanol,

and ethanol.

5.1.4. Limitations on Using the REFPROP v9.1 Database

Note that several limitations with mixture simulations still exist. Transport property calculations are not

supported for mixtures that include water with molar concentration over 5%. Changing the REFPROP

library version is not supported when running parallel ANSYS Fluent on heterogeneous (mixed windows-

linux) clusters


Physical Properties

Chapter 6: Heat Transfer

6.1. Enhanced Encapsulation for Shell Conduction and the S2S Model

In the parallel version of Fluent, you can specify that an enhanced routine is used for the encapsulation

of coupled walls that is a consequence of enabling shell conduction and/or the surface to surface (S2S)

radiation model. This enhanced encapsulation will produce partitions that yield better load balance and

smoother interfaces, which improves solver convergence. To use this option, first enable beta feature

access (as described in Introduction (p. 1)) and then enable the enhanced encapsulation using the

following text command:

define models shell-conduction enhanced-encapsulation?



Chapter 7: Heat Exchangers

7.1. Improved Curve Fitting for Heat-Exchanger Model

In the dual cell heat exchanger model, you can specify the performance data table (either heat transfer

or NTU) for calculating local heat transfer in the cell. If the operating mass flow rates fall within the

range of the mass flow rates provided in the performance data table, then linear interpolation has been

found to be the best method to calculate the NTU value. However, if the operating mass flow rates fall

outside the range specified in the performance data table, then the NTU value corresponding to the

maximum mass flow rate is taken if the operating mass flow rate is greater; otherwise the NTU value

corresponding to the minimum mass flow rate is taken if the operating mass flow rate is lower. Due to

this clipping of NTU values, unexpected heat transfer may occur. To avoid this, curve fitting allows you

to use the exponential curve for extrapolation. You can use the following flavors of exponential decay

curves for NTU versus mass flow rates.

(7.1)&= +

(7.2)& &

=

+

where a,b,c,d,e,g are user-specified coefficients and & is the primary mass flow rate.

To use Equation 7.1 (p. 19), you have to create a file named coefficient3.dat in your workingdirectory, which contains the coefficients a,b, and c for each auxiliary mass flow rate row by row. For

example, if the number of auxiliary mass flow rates is 3, then the file will read as

a1 b1 c1 a2 b2 c2 a3 b3 c3

ANSYS Fluent will read the file coefficient3.dat and use the coefficients in Equation 7.1 (p. 19)to compute the NTU value if the primary mass flow rate is out of range. If the primary mass flow rate

is within the range, the above coefficients will be ignored and linear interpolation will be used.

Similarly, to use Equation 7.2 (p. 19), you have to create a file named coefficient5.dat in yourworking directory, which contains the coefficients a,b,c,d, and g for each of the auxiliary mass flow rates

row by row. For example if the number of auxiliary mass flow rates is 3 then the file will read as

a1 b1 c1 d1 g1 a2 b2 c2 d2 g2 a3 b3 c3 d3 g3

7.1.1. Limitations

This feature can be used only for one heat exchanger since it can read only one file for coefficients.

This feature is available only with the dual cell heat exchanger model (see Using the Dual Cell Heat Ex-

changer Model in the User's Guide).

This feature cannot be used for interpolation. Linear interpolation is used for such cases.

Curves of the type outlined above can only be used for extrapolation.



7.1.2. Usage

Make sure you first enable beta feature access, as described in Introduction (p. 1). The feature can

be activated by setting an rpvar as follows:

For curve (1), enter (rpsetvar dc/extrapolation-method exponential3) in the console. Acoefficient file named coefficient3.datwill be created in the working directory when you performiterations.

For curve (2), enter (rpsetvar dc/extrapolation-method exponential5) in the console. Acoefficient file named coefficient5.dat will be created in the working directory when you performiterations.

To go back to the default extrapolation, use the following rpvar:

(rpsetvar dc/extrapolation-method default)

7.2. Alternate Formulation for the Dual Cell Heat Exchanger

It is a well known fact that the dual cell model depends on the resolution of the core meshes. If the

core mesh is very coarse, then accuracy is severely affected. Make sure you first enable beta feature

access, as described in Introduction (p. 1), then activate the alternate formulation for heat transfer

using the following text command:

define models heat-exchanger dual-cell-model alternate-formulation?

The results obtained using the alternate formulation is mesh independent and gives a reliable solution

even on very coarse meshes. Please note that the default formulation and alternate formulation results

are comparable on a sufficiently fine core mesh. Also the alternate formulation should not be used for

non-matching core meshes.

For background information about the dual cell heat exchanger, see Using the Dual Cell Heat Exchanger

Model in the User's Guide.


Heat Exchangers

Chapter 8: Turbulence

This chapter contains information relating to turbulence models implemented as beta features in ANSYS

Fluent 15.0.

8.1. Explicit Algebraic Reynolds Stress Model

8.2. Near-Wall Treatment for the Porous Media Interface

8.3. Near-Wall Treatment for Models

8.4. Buoyancy Effects on Omega-Based Turbulence Models

8.1. Explicit Algebraic Reynolds Stress Model

Explicit Algebraic Reynolds Stress Models (EARSM) represent an extension of the standard two-equation

models. They are derived from the Reynolds stress transport equations and give a nonlinear relation

between the Reynolds stresses and the mean strain-rate and vorticity tensors. Due to the higher order

terms, many flow phenomena are included in the model without the need to solve transport equations

for individual Reynolds stresses. The WJ-BSL-EARSM allows an extension of the BSL turbulence

model to capture the following flow effects:

Anisotropy of Reynolds stresses

Secondary flows

The BSL model is the basic model underlying the SST model. The BSL model is described in [4].

The implementation of the WJ-BSL-EARSM in ANSYS Fluent is based on the explicit algebraic Reynolds

stress model of Wallin and Johansson [1]. Differences from the original formulation by Wallin and Jo-

hansson are explained in the following text.

With EARSM, the Reynolds stresses are computed from the anisotropy tensor according to its definition:

= +

where the anisotropy tensor

is searched as a solution of the following implicit algebraic matrix

equation:

(8.1)= + = +

The coefficients

in this matrix equation depend on the

-coefficients of the pressure-strain term in

the underlying Reynolds stress transport model. Their values are selected here as

=1.245,

=0,

=1.8, !

=2.25.

The values of "#

, $%

, and &'

are the same as those used in the original model by Wallin and Johansson

[1]. As for the value of ()

, it is increased from 1.2 to 1.245 in the course of calibrating EARSM for its

use together with the BSL * + model.



and

denote the non-dimensional strain-rate and vorticity tensors, respectively. They are defined

as:

(8.2)=

+

(8.3)=

where the time-scale is given by:

(8.4)= = =

In order to arrive at an explicit solution of the Equation 8.1 (p. 21), the anisotropy tensor is expressed

as a polynomial based on the strain rate and the vorticity tensors as follows:

(8.5)

= + +

+ +

! ! " "! # ! " "! " "!

" "$ $! " "$ $! ! # !

% & '

(

The )-coefficients are evaluated to:

= * + ,-

= . /0 1 2 1 //3

4

5

= 6 78

= 9 : ; :

?

where the denominator Q is:

= @ A BB CD

E

F

The invariants, which appear in the formulation of the anisotropy tensor and the coefficients, are defined

by:

=GG H HI JK KJ

=LL M MN OP PO

=QR S T TUV VW WU

The model representation of the anisotropy tensor Equation 8.5 (p. 22) and its coefficients XY

follows

the original model by Wallin and Johansson [1] with two differences. First, the fourth order tensor

polynomial contribution (the Z[

\ \

term) is neglected in Equation 8.5 (p. 22). Second,


Turbulence

the tensor basis is slightly changed for convenience according to Apsley and Leschziner [2]. Although

the tensor basis is changed, the model remains algebraically equivalent to the original model of Wallin

and Johansson. The latter change results in correspondingly changed expressions for the coefficients

.

In three-dimensional flows, the equation to be solved for the function is of sixth order and no explicit

solution can be derived, whereas in two-dimensional mean flows the function can be derived from

a cubic equation, an analytic solution of which is recommended by Wallin and Johansson [1] also for

three-dimensional cases:

(8.6)=

+ + +

+

HgCl2 + H2 A = 22.0e+03, b = 0.0, E = 28770.0 (SI units) *

* Arguments: * char hg_func_name - UDF name * cell_t c - Cell index * Thread *t - Pointer to cell thread on * which the Hg rate is to be * applied * Pollut_Cell *Pollut - pointer to Pollut structure * Pollut_Parameter *Pollut_Par - pointer to * Pollut_Par structure * Hg_Parameter *Hg - pointer to Hg structure *

Description of Pollut_Par->pollut_io_pdf: 1. Pollut_Par->pollut_io_pdf == IN_PDF


Pollutants

All rate terms which are subjected to turbulent fluctuations must be included within this flag. 2. Pollut_Par->pollut_io_pdf == OUT_PDF All rate terms which must be outside of the pdf integration (are not affected by turbulence) must be included within this flag. e.g. Char contributions to pollutant formation. 3. Pollut_Par->pollut_io_pdf == SET_VAR To modify a parameter value, user may use this flag. e.g. Top temperature setting for pdf integration. 4. Pollut_Par->pollut_io_pdf == GET_VAR This flag may be used to obtain a mean rate of reaction or any other cell based value at the end of the source term computation.

Pollut_Par->nfstreams : Number of fuel streams Pollut->r_fuel_gls[i] : rate of volatile release for stream "i" per unit volume in kg/m3-sec Hg->Yhg_fuelvolat[i] : mass fraction of Hg in fuel/vol stream "i" Hg->Yhcl_fuelvolat[i] : mass fraction of HCl in fuel/vol stream "i" Hg->Ycl_fuelvolat[i] : mass fraction of Cl in fuel/vol stream "i" Hg->Yhg_char[i] : mass fraction of Hg in char stream "i" Hg->Yhcl_char[i] : mass fraction of HCl in char stream "i" Hg->Ycl_char[i] : mass fraction of Cl in char stream "i"*********************************************************************/

#include "udf.h"

DEFINE_HG_RATE(user_hg, c, t, Pollut, Pollut_Par, Hg){ int ifstream; real rf=0., rr = 0., kf1=0.; /*Rate_Const KF_HG = {1.204409e4, 0.0, 18000.0};*/ /* Hall (1991)*/ Rate_Const KF_HG = {2.2e4, 0.0, 28770.0}; /* Gasper et al. (1997)*/

POLLUT_FRATE(Pollut) = 0.0; POLLUT_RRATE(Pollut) = 0.0;

kf1 = ARRH(Pollut, KF_HG);

switch (Pollut_Par->pollut_io_pdf) { case IN_PDF: /* Include source terms other than those from char */ switch (POLLUT_EQN(Pollut_Par)) { case EQ_HG: /* Hg production */ for(ifstream=0; ifstreamnfstreams; ifstream++) { rf += Pollut->r_fuel_gls[ifstream]*Hg->Yhg_fuelvolat[ifstream] *1000./Pollut_Par->sp[IDX(HG)].mw; } rr = -kf1*MOLECON(Pollut, IDX(HG))*MOLECON(Pollut, IDX(HCL)); break; case EQ_HGCL2: rf = kf1*MOLECON(Pollut, IDX(HG))*MOLECON(Pollut, IDX(HCL)); break; case EQ_HCL: for(ifstream=0; ifstreamnfstreams; ifstream++) { rf +=Pollut->r_fuel_gls[ifstream]*Hg->Yhcl_fuelvolat[ifstream] *1000./Pollut_Par->sp[IDX(CL)].mw; } rr = -2.*kf1*MOLECON(Pollut, IDX(HG))*MOLECON(Pollut, IDX(HCL)); break; default: break; } break; case OUT_PDF: /* Char Contributions are not included in PDF integral */ switch (POLLUT_EQN(Pollut_Par)) { case EQ_HG: for(ifstream=0; ifstreamnfstreams; ifstream++) { if (Pollut_Par->pollut_type[ifstream] == FUEL_S) { rf += Pollut->r_char[ifstream]*Hg->Yhg_char[ifstream]*



Mercury Pollutant Formation

1000./Pollut_Par->sp[IDX(HG)].mw; break; /*char stream cannot be split at present*/ } } break; case EQ_HCL: for(ifstream=0; ifstreamnfstreams; ifstream++) { if (Pollut_Par->pollut_type[ifstream] == FUEL_S) { if (Hg->char_cl_conv[ifstream] == 0 || Hg->char_cl_conv[ifstream] == 2) { rf += Pollut->r_char[ifstream]*Hg->Yhcl_char[ifstream]* 1000./Pollut_Par->sp[IDX(CL)].mw; break; /*char stream cannot be split at present*/ } } } break; default: break; } break; case SET_VAR: /* Set a value at each cell before Hg rate computations */ break; case GET_VAR: /* Get values at the end of Hg computations */ break; default: /* Not used */ break; } POLLUT_FRATE(Pollut) = rf; POLLUT_RRATE(Pollut) = rr;}

10.3.5.4. Hooking DEFINE_HG_RATE UDFs

After you have interpreted or compiled your DEFINE_HG_Rate UDF, the name of the function yousupplied as a DEFINE macro argument will become visible and selectable in the Mercury Model dialogbox (Figure 10.12: The Mercury Model Dialog Box (p. 85)) in AN

fluent 15.0 beta features manual

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