ANSYS Fluent UDF Manual - Portal de Documentacion de software

592 Pages·2013·9.59 MB·English

by  R. H. Aungier

ANSYS Fluent UDF Manual
ANSYS, Inc. Release 15.0
Southpointe November 2013
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Table of Contents
Using This Manual...................................................................................................................................... xxi
1.The Contents of This Manual.............................................................................................................. xxi
2.The Contents of the Fluent Manuals.................................................................................................. xxii
3.Typographical Conventions............................................................................................................. xxiii
4. Mathematical Conventions.............................................................................................................. xxiv
5.Technical Support............................................................................................................................ xxv
1. Overview of User-Defined Functions (UDFs).......................................................................................... 1
1.1.What is a User-Defined Function?...................................................................................................... 1
1.2. Limitations ....................................................................................................................................... 2
1.3. Defining Your UDF Using DEFINE Macros......................................................................................... 2
1.3.1. Including the udf.h Header File in Your Source File................................................................. 3
1.4. Interpreting and Compiling UDFs...................................................................................................... 4
1.4.1. Compiled UDFs........................................................................................................................ 4
1.4.2. Interpreted UDFs ..................................................................................................................... 4
1.4.3. Differences Between Interpreted and Compiled UDFs............................................................... 5
1.5. Hooking UDFs to Your ANSYS Fluent Model....................................................................................... 6
1.6. Mesh Terminology............................................................................................................................ 6
1.7. Data Types in ANSYS Fluent............................................................................................................... 8
1.8. UDF Calling Sequence in the Solution Process................................................................................... 9
1.8.1. Pressure-Based Segregated Solver............................................................................................ 9
1.8.2. Pressure-Based Coupled Solver............................................................................................... 10
1.8.3. Density-Based Solver.............................................................................................................. 11
1.9. Special Considerations for Multiphase UDFs.................................................................................... 12
1.9.1. Multiphase-specific Data Types............................................................................................... 13
2.DEFINE Macros..................................................................................................................................... 15
2.1. Introduction ................................................................................................................................... 15
2.2. General Purpose DEFINE Macros................................................................................................... 15
2.2.1.DEFINE_ADJUST................................................................................................................. 16
2.2.1.1. Description ................................................................................................................... 16
2.2.1.2. Usage............................................................................................................................ 17
2.2.1.3. Example 1..................................................................................................................... 17
2.2.1.4. Example 2..................................................................................................................... 18
2.2.1.5. Hooking an Adjust UDF to ANSYS Fluent........................................................................ 18
2.2.2.DEFINE_DELTAT................................................................................................................. 18
2.2.2.1. Description ................................................................................................................... 18
2.2.2.2. Usage............................................................................................................................ 18
2.2.2.3. Example........................................................................................................................ 19
2.2.2.4. Hooking an Adaptive Time Step UDF to ANSYS Fluent.................................................... 19
2.2.3.DEFINE_EXECUTE_AT_END................................................................................................ 19
2.2.3.1. Description ................................................................................................................... 19
2.2.3.2. Usage............................................................................................................................ 20
2.2.3.3. Example........................................................................................................................ 20
2.2.3.4. Hooking an Execute-at-End UDF to ANSYS Fluent........................................................... 20
2.2.4.DEFINE_EXECUTE_AT_EXIT ............................................................................................. 21
2.2.4.1. Description ................................................................................................................... 21
2.2.4.2. Usage............................................................................................................................ 21
2.2.4.3. Hooking an Execute-at-Exit UDF to ANSYS Fluent........................................................... 21
2.2.5.DEFINE_EXECUTE_FROM_GUI........................................................................................... 21
2.2.5.1. Description ................................................................................................................... 21
2.2.5.2. Usage............................................................................................................................ 21
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2.2.5.3. Example........................................................................................................................ 22
2.2.5.4. Hooking an Execute From GUI UDF to ANSYS Fluent....................................................... 23
2.2.6.DEFINE_EXECUTE_ON_LOADING....................................................................................... 23
2.2.6.1. Description ................................................................................................................... 23
2.2.6.2. Usage............................................................................................................................ 23
2.2.6.3. Example 1..................................................................................................................... 23
2.2.6.4. Example 2..................................................................................................................... 24
2.2.6.5. Hooking an Execute On Loading UDF to ANSYS Fluent................................................... 25
2.2.7.DEFINE_EXECUTE_AFTER_CASE/DATA............................................................................ 25
2.2.7.1. Description ................................................................................................................... 25
2.2.7.2. Usage............................................................................................................................ 25
2.2.7.3. Example........................................................................................................................ 26
2.2.7.4. Hooking an Execute After Reading Case and Data File UDF to ANSYS Fluent.................... 26
2.2.8.DEFINE_INIT...................................................................................................................... 26
2.2.8.1. Description ................................................................................................................... 26
2.2.8.2. Usage............................................................................................................................ 26
2.2.8.3. Example........................................................................................................................ 27
2.2.8.4. Hooking an Initialization UDF to ANSYS Fluent............................................................... 27
2.2.9.DEFINE_ON_DEMAND........................................................................................................... 27
2.2.9.1. Description ................................................................................................................... 27
2.2.9.2. Usage............................................................................................................................ 28
2.2.9.3. Example........................................................................................................................ 28
2.2.9.4. Hooking an On-Demand UDF to ANSYS Fluent............................................................... 29
2.2.10.DEFINE_OUTPUT_PARAMETER ......................................................................................... 29
2.2.10.1. Description.................................................................................................................. 29
2.2.10.2. Usage.......................................................................................................................... 29
2.2.10.3. Example...................................................................................................................... 30
2.2.10.4. Hooking an Output Parameter UDF to ANSYS Fluent.................................................... 30
2.2.11.DEFINE_RW_FILE............................................................................................................. 31
2.2.11.1. Description.................................................................................................................. 31
2.2.11.2. Usage.......................................................................................................................... 31
2.2.11.3. Example...................................................................................................................... 31
2.2.11.4. Hooking a Read/Write Case or Data File UDF to ANSYS Fluent....................................... 32
2.3. Model-Specific DEFINE Macros...................................................................................................... 32
2.3.1.DEFINE_ANISOTROPIC_CONDUCTIVITY.......................................................................... 38
2.3.1.1. Description ................................................................................................................... 38
2.3.1.2. Usage............................................................................................................................ 38
2.3.1.3. Example........................................................................................................................ 38
2.3.1.4. Hooking an Anisotropic Conductivity UDF to ANSYS Fluent............................................ 40
2.3.2.DEFINE_CHEM_STEP........................................................................................................... 40
2.3.2.1. Description ................................................................................................................... 40
2.3.2.2. Usage............................................................................................................................ 40
2.3.2.3. Example........................................................................................................................ 41
2.3.2.4. Hooking a Chemistry Step UDF to ANSYS Fluent............................................................. 41
2.3.3.DEFINE_CPHI...................................................................................................................... 41
2.3.3.1. Description ................................................................................................................... 41
2.3.3.2. Usage............................................................................................................................ 41
2.3.3.3. Hooking a Mixing Constant UDF to ANSYS Fluent........................................................... 42
2.3.4.DEFINE_DIFFUSIVITY...................................................................................................... 42
2.3.4.1. Description ................................................................................................................... 42
2.3.4.2. Usage............................................................................................................................ 42
2.3.4.3. Example........................................................................................................................ 43
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2.3.4.4. Hooking a Diffusivity UDF to ANSYS Fluent.................................................................... 43
2.3.5.DEFINE_DOM_DIFFUSE_REFLECTIVITY.......................................................................... 43
2.3.5.1. Description ................................................................................................................... 43
2.3.5.2. Usage............................................................................................................................ 43
2.3.5.3. Example........................................................................................................................ 44
2.3.5.4. Hooking a Discrete Ordinates Model (DOM) Diffuse Reflectivity UDF to ANSYS Fluent..... 45
2.3.6.DEFINE_DOM_SOURCE ........................................................................................................ 45
2.3.6.1. Description ................................................................................................................... 45
2.3.6.2. Usage............................................................................................................................ 45
2.3.6.3. Example........................................................................................................................ 46
2.3.6.4. Hooking a DOM Source UDF to ANSYS Fluent................................................................. 46
2.3.7.DEFINE_DOM_SPECULAR_REFLECTIVITY ....................................................................... 46
2.3.7.1. Description ................................................................................................................... 46
2.3.7.2. Usage............................................................................................................................ 46
2.3.7.3. Example........................................................................................................................ 47
2.3.7.4. Hooking a Discrete Ordinates Model (DOM) Specular Reflectivity UDF to ANSYS Flu-
ent ........................................................................................................................................... 48
2.3.8.DEFINE_ECFM_SPARK_SOURCE......................................................................................... 48
2.3.8.1. Description ................................................................................................................... 48
2.3.8.2. Usage............................................................................................................................ 48
2.3.8.3. Example........................................................................................................................ 49
2.3.8.4. Hooking an ECFM Spark Source UDF to ANSYS Fluent..................................................... 49
2.3.9.DEFINE_EMISSIVITY_WEIGHTING_FACTOR................................................................... 49
2.3.9.1. Description ................................................................................................................... 49
2.3.9.2. Usage............................................................................................................................ 49
2.3.9.3. Example........................................................................................................................ 50
2.3.9.4. Hooking an Emissivity Weighting Factor UDF to ANSYS Fluent........................................ 50
2.3.10.DEFINE_ZONE_MOTION .................................................................................................... 50
2.3.10.1. Description.................................................................................................................. 50
2.3.10.2. Usage.......................................................................................................................... 50
2.3.10.3. Example...................................................................................................................... 51
2.3.10.4. Hooking a Frame Motion UDF to ANSYS Fluent............................................................. 52
2.3.11.DEFINE_GRAY_BAND_ABS_COEFF................................................................................... 52
2.3.11.1. Description.................................................................................................................. 52
2.3.11.2. Usage.......................................................................................................................... 52
2.3.11.3. Example...................................................................................................................... 52
2.3.11.4. Hooking a Gray Band Coefficient UDF to ANSYS Fluent................................................. 53
2.3.12.DEFINE_HEAT_FLUX......................................................................................................... 53
2.3.12.1. Description.................................................................................................................. 53
2.3.12.2. Usage.......................................................................................................................... 53
2.3.12.3. Example...................................................................................................................... 54
2.3.12.4. Hooking a Heat Flux UDF to ANSYS Fluent.................................................................... 54
2.3.13.DEFINE_IGNITE_SOURCE................................................................................................ 54
2.3.13.1. Description.................................................................................................................. 54
2.3.13.2. Usage.......................................................................................................................... 54
2.3.13.3. Example...................................................................................................................... 55
2.3.13.4. Hooking an Ignition Source UDF to ANSYS Fluent......................................................... 56
2.3.14.DEFINE_NET_REACTION_RATE....................................................................................... 56
2.3.14.1. Description.................................................................................................................. 56
2.3.14.2. Usage.......................................................................................................................... 57
2.3.14.3. Example...................................................................................................................... 57
2.3.14.4. Hooking a Net Reaction Rate UDF to ANSYS Fluent....................................................... 58
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2.3.15.DEFINE_NOX_RATE........................................................................................................... 58
2.3.15.1. Description.................................................................................................................. 58
2.3.15.2. Usage.......................................................................................................................... 59
2.3.15.3. Example 1 ................................................................................................................... 60
2.3.15.4. Example 2 ................................................................................................................... 61
2.3.15.5. Hooking a NOx Rate UDF to ANSYS Fluent.................................................................... 62
2.3.16.DEFINE_PDF_TABLE......................................................................................................... 62
2.3.16.1. Description.................................................................................................................. 62
2.3.16.2. Usage.......................................................................................................................... 63
2.3.16.3. Example 1 ................................................................................................................... 65
2.3.16.4. Example 2 ................................................................................................................... 66
2.3.16.5. Hooking a DEFINE_PDF_TABLE UDF to ANSYS Fluent.................................................... 68
2.3.17.DEFINE_PR_RATE............................................................................................................. 68
2.3.17.1. Description.................................................................................................................. 68
2.3.17.2. Usage.......................................................................................................................... 68
2.3.17.3. Auxiliary function........................................................................................................ 69
2.3.17.4. Example 1 ................................................................................................................... 69
2.3.17.5. Example 2 ................................................................................................................... 70
2.3.17.6. Hooking a Particle Reaction Rate UDF to ANSYS Fluent................................................. 71
2.3.18.DEFINE_PRANDTL UDFs.................................................................................................... 71
2.3.18.1.DEFINE_PRANDTL_D................................................................................................ 72
2.3.18.2. Description.................................................................................................................. 72
2.3.18.3. Usage.......................................................................................................................... 72
2.3.18.4. Example...................................................................................................................... 72
2.3.18.5. Hooking a Prandtl Number UDF to ANSYS Fluent.......................................................... 72
2.3.18.6.DEFINE_PRANDTL_K................................................................................................ 72
2.3.18.7. Description.................................................................................................................. 72
2.3.18.8. Usage.......................................................................................................................... 72
2.3.18.9. Example...................................................................................................................... 73
2.3.18.10. Hooking a Prandtl Number UDF to ANSYS Fluent........................................................ 74
2.3.18.11.DEFINE_PRANDTL_O.............................................................................................. 74
2.3.18.12. Description................................................................................................................ 74
2.3.18.13. Usage........................................................................................................................ 74
2.3.18.14. Example .................................................................................................................... 75
2.3.18.15. Hooking a Prandtl Number UDF to ANSYS Fluent........................................................ 75
2.3.18.16.DEFINE_PRANDTL_T.............................................................................................. 75
2.3.18.17. Description................................................................................................................ 75
2.3.18.18. Usage........................................................................................................................ 75
2.3.18.19. Example .................................................................................................................... 75
2.3.18.20. Hooking a Prandtl Number UDF to ANSYS Fluent........................................................ 76
2.3.18.21.DEFINE_PRANDTL_T_WALL................................................................................... 76
2.3.18.22. Description................................................................................................................ 76
2.3.18.23. Usage........................................................................................................................ 76
2.3.18.24. Example .................................................................................................................... 76
2.3.18.25. Hooking a Prandtl Number UDF to ANSYS Fluent........................................................ 76
2.3.19.DEFINE_PROFILE............................................................................................................. 77
2.3.19.1. Description.................................................................................................................. 77
2.3.19.2. Usage.......................................................................................................................... 77
2.3.19.3. Example 1 - Pressure Profile......................................................................................... 78
2.3.19.4. Example 2 - Velocity,Turbulent Kinetic Energy, and Turbulent Dissipation Rate Pro-
files .......................................................................................................................................... 79
2.3.19.5. Example 3 - Fixed Velocity UDF..................................................................................... 81
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2.3.19.6. Example 4 - Wall Heat Generation Rate Profile.............................................................. 83
2.3.19.7. Example 5 - Beam Direction Profile at Semi-Transparent Walls....................................... 83
2.3.19.8. Example 6 - Viscous Resistance Profile in a Porous Zone................................................ 84
2.3.19.9. Example 7 - Porous Resistance Direction Vector............................................................ 85
2.3.19.10. Example 8 -Target Mass Flow Rate UDF as a Function of Physical Flow Time................. 85
2.3.19.11. Example 9 - Mass Flow Rate UDF for the Mass Flow Inlet............................................. 86
2.3.19.12. Hooking a Boundary Profile UDF to ANSYS Fluent....................................................... 86
2.3.20.DEFINE_PROPERTY UDFs.................................................................................................. 86
2.3.20.1. Description.................................................................................................................. 86
2.3.20.2. Usage.......................................................................................................................... 88
2.3.20.3. Auxiliary Utilities.......................................................................................................... 88
2.3.20.4. Example 1 - Temperature-dependent Viscosity Property............................................... 90
2.3.20.5. Example 2 - User-defined Mixing Law for Thermal Conductivity.................................... 90
2.3.20.6. Example 3 - Surface Tension Coefficient UDF................................................................ 91
2.3.20.7. Example 4 - Density Function for Compressible Liquids................................................ 91
2.3.20.8. Hooking a Property UDF to ANSYS Fluent..................................................................... 92
2.3.21.DEFINE_REACTING_CHANNEL_BC................................................................................... 92
2.3.21.1. Description.................................................................................................................. 92
2.3.21.2. Usage.......................................................................................................................... 92
2.3.21.3. Example...................................................................................................................... 93
2.3.21.4. Hooking a Reacting Channel Solver UDF to ANSYS Fluent............................................. 94
2.3.22.DEFINE_REACTING_CHANNEL_SOLVER.......................................................................... 94
2.3.22.1. Description.................................................................................................................. 94
2.3.22.2. Usage.......................................................................................................................... 94
2.3.22.3. Example...................................................................................................................... 95
2.3.22.4. Hooking a Reacting Channel Solver UDF to ANSYS Fluent............................................. 97
2.3.23.DEFINE_SCAT_PHASE_FUNC ........................................................................................... 97
2.3.23.1. Description.................................................................................................................. 97
2.3.23.2. Usage.......................................................................................................................... 97
2.3.23.3. Example...................................................................................................................... 98
2.3.23.4. Hooking a Scattering Phase UDF to ANSYS Fluent......................................................... 99
2.3.24.DEFINE_SOLAR_INTENSITY ........................................................................................... 99
2.3.24.1. Description.................................................................................................................. 99
2.3.24.2. Usage.......................................................................................................................... 99
2.3.24.3. Example .................................................................................................................... 100
2.3.24.4. Hooking a Solar Intensity UDF to ANSYS Fluent.......................................................... 100
2.3.25.DEFINE_SOLIDIFICATION_PARAMS ............................................................................ 100
2.3.25.1. Description................................................................................................................ 100
2.3.25.2. Usage........................................................................................................................ 100
2.3.25.3. Example .................................................................................................................... 101
2.3.25.4. Hooking a Solidification Parameter UDF in ANSYS Fluent............................................ 101
2.3.26.DEFINE_SOOT_OXIDATION_RATE................................................................................. 101
2.3.26.1. Description................................................................................................................ 101
2.3.26.2. Usage........................................................................................................................ 101
2.3.26.3. Example: Soot Oxidation Rate..................................................................................... 102
2.3.26.4. Hooking a Soot Oxidation Rate UDF to ANSYS Fluent.................................................. 103
2.3.27.DEFINE_SOOT_PRECURSOR............................................................................................ 103
2.3.27.1. Description................................................................................................................ 103
2.3.27.1.1. Usage ............................................................................................................... 103
2.3.27.1.2. Example: Soot Precursor.................................................................................... 104
2.3.27.1.3. Hooking a SOOT_PRECURSOR UDF to ANSYS Fluent........................................... 104
2.3.28.DEFINE_SOURCE ............................................................................................................. 104
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2.3.28.1. Description................................................................................................................ 104
2.3.28.2. Usage........................................................................................................................ 105
2.3.28.3. Example 1 - Source Term Addition.............................................................................. 105
2.3.28.4. Example 2 - Degassing Boundary Condition............................................................... 106
2.3.28.5. Hooking a Source UDF to ANSYS Fluent...................................................................... 108
2.3.29.DEFINE_SOX_RATE......................................................................................................... 108
2.3.29.1. Description................................................................................................................ 108
2.3.29.2. Usage........................................................................................................................ 108
2.3.29.3. Example 1.................................................................................................................. 109
2.3.29.4. Example 2.................................................................................................................. 111
2.3.29.5. Hooking a SOx Rate UDF to ANSYS Fluent................................................................... 112
2.3.30.DEFINE_SPARK_GEOM (R14.5 spark model)......................................................... 112
2.3.30.1. Description................................................................................................................ 112
2.3.30.2. Usage........................................................................................................................ 113
2.3.30.3. Example .................................................................................................................... 113
2.3.30.4. Hooking a Spark Geometry UDF to ANSYS Fluent....................................................... 115
2.3.31.DEFINE_SPECIFIC_HEAT.............................................................................................. 115
2.3.31.1. Description................................................................................................................ 115
2.3.31.2. Usage........................................................................................................................ 115
2.3.31.3. Example .................................................................................................................... 116
2.3.31.4. Hooking a Specific Heat UDF to ANSYS Fluent............................................................ 116
2.3.32.DEFINE_SR_RATE ........................................................................................................... 116
2.3.32.1. Description................................................................................................................ 116
2.3.32.2. Usage........................................................................................................................ 116
2.3.32.3. Example 1 - Surface Reaction Rate Using Species Mass Fractions................................. 117
2.3.32.4. Example 2 - Surface Reaction Rate Using Site Species................................................. 118
2.3.32.5. Hooking a Surface Reaction Rate UDF to ANSYS Fluent............................................... 118
2.3.33.DEFINE_THICKENED_FLAME_MODEL ............................................................................ 118
2.3.33.1. Description................................................................................................................ 118
2.3.33.2. Usage........................................................................................................................ 119
2.3.33.3. Example - Thickened Flame Model............................................................................. 119
2.3.33.4. Hooking a Thickened Flame Model UDF to ANSYS Fluent............................................ 119
2.3.34.DEFINE_TRANS UDFs....................................................................................................... 120
2.3.34.1.DEFINE_TRANS_FLENGTH ..................................................................................... 120
2.3.34.2. Description................................................................................................................ 120
2.3.34.3. Usage........................................................................................................................ 120
2.3.34.4. Example .................................................................................................................... 120
2.3.34.5. Hooking a Transition Correlation UDF to ANSYS Fluent............................................... 120
2.3.34.6.DEFINE_TRANS_RETHETA_C................................................................................. 120
2.3.34.7. Description................................................................................................................ 120
2.3.34.8. Usage........................................................................................................................ 121
2.3.34.9. Example .................................................................................................................... 121
2.3.34.10. Hooking a Transition Correlation UDF to ANSYS Fluent............................................. 121
2.3.34.11.DEFINE_TRANS_RETHETA_T............................................................................... 121
2.3.34.12. Description.............................................................................................................. 121
2.3.34.13. Usage...................................................................................................................... 121
2.3.34.14. Example .................................................................................................................. 122
2.3.34.15. Hooking a Transition Correlation UDF to ANSYS Fluent............................................. 122
2.3.35.DEFINE_TRANSIENT_PROFILE ..................................................................................... 122
2.3.35.1. Description................................................................................................................ 122
2.3.35.2. Usage........................................................................................................................ 122
2.3.35.3. Example .................................................................................................................... 123
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2.3.35.4. Hooking a Transient Profile UDF to ANSYS Fluent........................................................ 123
2.3.36.DEFINE_TURB_PREMIX_SOURCE................................................................................... 123
2.3.36.1. Description................................................................................................................ 123
2.3.36.2. Usage........................................................................................................................ 123
2.3.36.3. Example .................................................................................................................... 124
2.3.36.4. Hooking a Turbulent Premixed Source UDF to ANSYS Fluent....................................... 125
2.3.37.DEFINE_TURB_SCHMIDT UDF......................................................................................... 125
2.3.37.1. Description................................................................................................................ 125
2.3.37.2. Usage........................................................................................................................ 125
2.3.37.3. Example .................................................................................................................... 125
2.3.37.4. Hooking a Turbulent Schmidt Number UDF to ANSYS Fluent...................................... 126
2.3.38.DEFINE_TURBULENT_VISCOSITY................................................................................. 126
2.3.38.1. Description................................................................................................................ 126
2.3.38.2. Usage........................................................................................................................ 126
2.3.38.3. Example 1 - Single Phase Turbulent Viscosity UDF....................................................... 126
2.3.38.4. Example 2 - Multiphase Turbulent Viscosity UDF......................................................... 127
2.3.38.5. Hooking a Turbulent Viscosity UDF to ANSYS Fluent................................................... 127
2.3.39.DEFINE_VR_RATE ........................................................................................................... 128
2.3.39.1. Description................................................................................................................ 128
2.3.39.2. Usage........................................................................................................................ 128
2.3.39.3. Example 1.................................................................................................................. 128
2.3.39.4. Example 2.................................................................................................................. 129
2.3.39.5. Hooking a Volumetric Reaction Rate UDF to ANSYS Fluent.......................................... 130
2.3.40.DEFINE_WALL_FUNCTIONS............................................................................................ 130
2.3.40.1. Description................................................................................................................ 130
2.3.40.2. Usage........................................................................................................................ 130
2.3.40.3. Example .................................................................................................................... 131
2.3.40.4. Hooking a Wall Function UDF to ANSYS Fluent........................................................... 131
2.3.41.DEFINE_WSGGM_ABS_COEFF.......................................................................................... 131
2.3.41.1. Description................................................................................................................ 131
2.3.41.2. Usage........................................................................................................................ 132
2.3.41.3. Example .................................................................................................................... 132
2.3.41.4. Hooking a Wall Function UDF to ANSYS Fluent........................................................... 133
2.4. Multiphase DEFINE Macros.......................................................................................................... 133
2.4.1.DEFINE_BOILING_PROPERTY ......................................................................................... 135
2.4.1.1. Description.................................................................................................................. 135
2.4.1.2. Usage.......................................................................................................................... 135
2.4.1.3. Example...................................................................................................................... 136
2.4.1.4. Hooking a Boiling Property UDF to ANSYS Fluent......................................................... 136
2.4.2.DEFINE_CAVITATION_RATE ........................................................................................... 136
2.4.2.1. Description.................................................................................................................. 136
2.4.2.2. Usage.......................................................................................................................... 137
2.4.2.3. Example...................................................................................................................... 137
2.4.2.4. Hooking a Cavitation Rate UDF to ANSYS Fluent........................................................... 138
2.4.3.DEFINE_EXCHANGE_PROPERTY....................................................................................... 138
2.4.3.1. Description.................................................................................................................. 138
2.4.3.2. Usage.......................................................................................................................... 139
2.4.3.3. Example 1 - Custom Drag Law...................................................................................... 140
2.4.3.4. Example 2 - Custom Lift Law........................................................................................ 141
2.4.3.5. Example 3- Heat Transfer.............................................................................................. 142
2.4.3.6. Example 4- Custom Interfacial Area.............................................................................. 142
2.4.3.7. Hooking an Exchange Property UDF to ANSYS Fluent................................................... 142
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UDF Manual
2.4.4.DEFINE_HET_RXN_RATE.................................................................................................. 143
2.4.4.1. Description.................................................................................................................. 143
2.4.4.2. Usage.......................................................................................................................... 143
2.4.4.3. Example...................................................................................................................... 144
2.4.4.4. Hooking a Heterogeneous Reaction Rate UDF to ANSYS Fluent..................................... 145
2.4.5.DEFINE_LINEARIZED_MASS_TRANSFER........................................................................ 146
2.4.5.1. Description.................................................................................................................. 146
2.4.5.2. Usage.......................................................................................................................... 146
2.4.5.3. Example...................................................................................................................... 148
2.4.5.4. Hooking a Linearized Mass Transfer UDF to ANSYS Fluent............................................. 149
2.4.6.DEFINE_MASS_TRANSFER................................................................................................ 149
2.4.6.1. Description.................................................................................................................. 149
2.4.6.2. Usage.......................................................................................................................... 149
2.4.6.3. Example...................................................................................................................... 150
2.4.6.4. Hooking a Mass Transfer UDF to ANSYS Fluent.............................................................. 151
2.4.7.DEFINE_VECTOR_EXCHANGE_PROPERTY........................................................................ 151
2.4.7.1. Description.................................................................................................................. 151
2.4.7.2. Usage.......................................................................................................................... 151
2.4.7.3. Example 1 — Custom Slip Velocity............................................................................... 152
2.4.7.4. Example 2 — Custom Turbulent Dispersion.................................................................. 153
2.4.7.5. Hooking a Vector Exchange Property UDF to ANSYS Fluent........................................... 153
2.5. Discrete Phase Model (DPM) DEFINE Macros................................................................................ 153
2.5.1.DEFINE_DPM_BC ............................................................................................................... 155
2.5.1.1. Description.................................................................................................................. 155
2.5.1.2. Usage.......................................................................................................................... 155
2.5.1.3. Example 1 ................................................................................................................... 155
2.5.1.4. Example 2 ................................................................................................................... 157
2.5.1.5. Hooking a DPM Boundary Condition UDF to ANSYS Fluent........................................... 159
2.5.2.DEFINE_DPM_BODY_FORCE.............................................................................................. 159
2.5.2.1. Description.................................................................................................................. 159
2.5.2.2. Usage.......................................................................................................................... 159
2.5.2.3. Example...................................................................................................................... 160
2.5.2.4. Hooking a DPM Body Force UDF to ANSYS Fluent......................................................... 161
2.5.3.DEFINE_DPM_DRAG........................................................................................................... 161
2.5.3.1. Description.................................................................................................................. 161
2.5.3.2. Usage.......................................................................................................................... 161
2.5.3.3. Example...................................................................................................................... 162
2.5.3.4. Hooking a DPM Drag Coefficient UDF to ANSYS Fluent................................................. 162
2.5.4.DEFINE_DPM_EROSION .................................................................................................... 163
2.5.4.1. Description.................................................................................................................. 163
2.5.4.2. Usage.......................................................................................................................... 163
2.5.4.3. Example...................................................................................................................... 163
2.5.4.4. Hooking an Erosion/Accretion UDF to ANSYS Fluent..................................................... 166
2.5.5.DEFINE_DPM_HEAT_MASS................................................................................................ 166
2.5.5.1. Description.................................................................................................................. 166
2.5.5.2. Usage.......................................................................................................................... 167
2.5.5.3. Example...................................................................................................................... 167
2.5.5.4. Hooking a DPM Particle Heat and Mass Transfer UDF to ANSYS Fluent........................... 169
2.5.6.DEFINE_DPM_INJECTION_INIT..................................................................................... 169
2.5.6.1. Description.................................................................................................................. 169
2.5.6.2. Usage.......................................................................................................................... 169
2.5.6.3. Example...................................................................................................................... 170
Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information
x of ANSYS, Inc. and its subsidiaries and affiliates.