ANSYS Fluent Meshing User's Guide - Portal de Documentacion de

700 Pages·2013·12.43 MB·English

ANSYS Fluent Meshing User's Guide
ANSYS, Inc. Release 15.0
Southpointe November 2013
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Table of Contents
1. Using This Manual................................................................................................................................... 1
1.1.The Contents of This Manual............................................................................................................. 1
1.2.Typographical Conventions Used In This Manual................................................................................ 2
1.3. Contacting Technical Support........................................................................................................... 3
2. Introduction to Meshing Mode in ANSYS Fluent.................................................................................... 7
2.1. Meshing Approach........................................................................................................................... 7
2.2. Program Capabilities......................................................................................................................... 7
2.3. ANSYS Fluent Documentation........................................................................................................... 8
2.3.1. Accessing the ANSYS Fluent Documentation............................................................................ 8
2.3.1.1. Accessing the Documentation Files Using the ANSYS Help Viewer.................................... 9
2.3.1.2. Downloading and Installing the PDF Documentation Files................................................ 9
3. Starting and Executing ANSYS Fluent in Meshing Mode...................................................................... 11
3.1. Starting ANSYS Fluent in Meshing Mode......................................................................................... 11
3.1.1. Using Fluent Launcher............................................................................................................ 11
3.1.2. Starting on a Windows System................................................................................................ 13
3.1.3. Starting on a Linux System..................................................................................................... 13
3.1.4. Starting the Dual Process Build............................................................................................... 13
3.1.5. Startup Options ..................................................................................................................... 14
3.2. Parallel Processing in Meshing Mode............................................................................................... 15
3.2.1. Dynamically Spawning Processes Between Fluent Meshing and Fluent Solution Modes........... 16
3.3. Exiting the Program........................................................................................................................ 17
4. Graphical User Interface....................................................................................................................... 19
4.1. GUI Components............................................................................................................................ 19
4.1.1. Menu Bar............................................................................................................................... 20
4.1.2.Toolbars................................................................................................................................. 21
4.1.2.1.The Mode Toolbar.......................................................................................................... 21
4.1.2.2.The Standard Toolbar..................................................................................................... 22
4.1.2.3.The Graphics Toolbars.................................................................................................... 23
4.1.2.4.The Objects Toolbar....................................................................................................... 24
4.1.3.The Navigation Pane............................................................................................................... 24
4.1.4.Task Pages.............................................................................................................................. 25
4.1.5.The Console........................................................................................................................... 25
4.1.6. Dialog Boxes.......................................................................................................................... 26
4.1.6.1. Controls of a Dialog Box................................................................................................. 27
4.1.6.2. Special Dialog Boxes...................................................................................................... 31
4.1.7. Graphics Windows.................................................................................................................. 37
4.1.7.1. Printing the Contents of the Graphics Window (Windows Systems Only)......................... 38
4.1.7.2.The Page Setup Dialog Box............................................................................................ 38
4.2. Customizing the GUI (Linux Systems).............................................................................................. 40
4.3. Using the GUI Help System.............................................................................................................. 41
4.3.1.Task Page and Dialog Box Help............................................................................................... 42
4.3.2. Context-Sensitive Help (Linux Only)........................................................................................ 42
4.3.3. Opening the User’s Guide Table of Contents............................................................................ 42
4.3.4. Opening the Reference Guide................................................................................................. 43
4.3.5. Accessing Printable Manuals.................................................................................................. 44
4.3.6. Help for Text Interface Commands.......................................................................................... 44
4.3.7. Using Help............................................................................................................................. 44
4.3.8. Accessing Online Technical Resources..................................................................................... 44
4.3.9. Obtaining a Listing of Other License Users.............................................................................. 45
4.3.10.Version and Release Information........................................................................................... 45
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5.Text User Interface................................................................................................................................ 47
5.1.Text Menu System........................................................................................................................... 47
5.1.1. Command Abbreviation......................................................................................................... 48
5.1.2. Scheme Evaluation................................................................................................................. 49
5.1.3. Aliases ................................................................................................................................... 49
5.2.Text Prompt System........................................................................................................................ 50
5.2.1. Numbers................................................................................................................................ 50
5.2.2. Booleans................................................................................................................................ 51
5.2.3. Strings................................................................................................................................... 51
5.2.4. Symbols................................................................................................................................. 51
5.2.5. Filenames .............................................................................................................................. 52
5.2.6. Lists....................................................................................................................................... 52
5.2.7. Evaluation.............................................................................................................................. 53
5.2.8. Default Value Binding............................................................................................................. 53
5.3. Interrupts ....................................................................................................................................... 53
5.4. System Commands......................................................................................................................... 53
5.4.1. System Commands for LINUX-based Operating Systems......................................................... 53
5.4.2. System Commands for Windows-based Operating Systems..................................................... 54
5.5.Text Menu Input from Character Strings.......................................................................................... 55
5.6. Using the Text Interface Help System............................................................................................... 55
6. Reading and Writing Files..................................................................................................................... 57
6.1. Shortcuts for Reading and Writing Files........................................................................................... 57
6.1.1. Default File Suffixes................................................................................................................ 57
6.1.2. Binary Files............................................................................................................................. 58
6.1.3. Detecting File Format............................................................................................................. 58
6.1.4. Recent File List....................................................................................................................... 58
6.1.5. Reading and Writing Compressed Files................................................................................... 58
6.1.5.1. Reading Compressed Files............................................................................................. 58
6.1.5.2.Writing Compressed Files............................................................................................... 59
6.1.6.Tilde Expansion (LINUX Systems Only).................................................................................... 59
6.1.7. Disabling the Overwrite Confirmation Prompt........................................................................ 59
6.1.8.Toolbar Buttons...................................................................................................................... 59
6.2. Mesh Files....................................................................................................................................... 60
6.2.1. Reading Boundary Mesh Files................................................................................................. 61
6.2.1.1. Reading Multiple Boundary Mesh Files........................................................................... 61
6.2.2. Reading Mesh Files................................................................................................................. 61
6.2.2.1. Reading Multiple Mesh Files .......................................................................................... 61
6.2.2.2. Reading 2D Mesh Files in the 3D Version of ANSYS Fluent............................................... 62
6.2.3. Reading Faceted Geometry Files from ANSYS Workbench in ANSYS Fluent.............................. 62
6.2.4. Appending Mesh Files............................................................................................................ 62
6.2.5.Writing Mesh Files.................................................................................................................. 63
6.2.6.Writing Boundary Mesh Files.................................................................................................. 63
6.3. Case Files........................................................................................................................................ 63
6.3.1. Reading Case Files.................................................................................................................. 64
6.3.1.1. Reading Multiple Case Files ........................................................................................... 64
6.3.2.Writing Case Files................................................................................................................... 64
6.4. Size-Field Files ................................................................................................................................ 65
6.4.1. Reading Size-Field Files.......................................................................................................... 65
6.4.2.Writing Size-Field Files............................................................................................................ 66
6.5. Reading Scheme Source Files.......................................................................................................... 66
6.6. Creating and Reading Journal Files.................................................................................................. 66
6.7. Creating Transcript Files.................................................................................................................. 68
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6.8. Domain Files................................................................................................................................... 69
6.9. Importing Files ............................................................................................................................... 69
6.9.1. ANSYS Prep7 Files.................................................................................................................. 70
6.9.2. CGNS Files.............................................................................................................................. 70
6.9.3. Importing FIDAP Neutral Mesh Files........................................................................................ 70
6.9.4. Importing GAMBIT Neutral Mesh Files..................................................................................... 71
6.9.5. HYPERMESH ASCII Files........................................................................................................... 71
6.9.6. I-deas Universal Files.............................................................................................................. 71
6.9.7. NASTRAN Files....................................................................................................................... 72
6.9.8. PATRAN Neutral Files.............................................................................................................. 72
6.9.9. Importing CAD Files............................................................................................................... 72
6.9.9.1.Text Commands for Importing CAD Files........................................................................ 76
6.9.10. Grid Import Filter Options..................................................................................................... 78
6.9.10.1.Text Commands for Setting Filter Options..................................................................... 78
6.10. Exporting STL Files........................................................................................................................ 78
6.11. Saving Picture Files....................................................................................................................... 78
6.11.1. Using the Save Picture Dialog Box......................................................................................... 78
6.11.2.Text Interface for Saving Picture Files.................................................................................... 82
6.12.The .tgrid File................................................................................................................................ 83
6.13. Exiting the Meshing Mode............................................................................................................ 84
7. Size Functions....................................................................................................................................... 85
7.1.Types of Size Functions................................................................................................................... 85
7.1.1. Curvature Size Function.......................................................................................................... 86
7.1.2. Proximity Size Function.......................................................................................................... 87
7.1.3. Meshed Size Function............................................................................................................ 90
7.1.4. Hard Size Function................................................................................................................. 91
7.1.5. Soft Size Function.................................................................................................................. 91
7.1.6. Body of Influence Size Function.............................................................................................. 92
7.2. Defining Size Functions................................................................................................................... 93
7.2.1. Creating Default Size Functions.............................................................................................. 94
7.2.2. Computing the Size Field........................................................................................................ 95
7.2.2.1. Size Field Files................................................................................................................ 95
7.2.2.2. Using Size Field Filters.................................................................................................... 95
7.2.2.3.Visualizing Sizes............................................................................................................. 96
7.3. Using Size Functions/Size Field........................................................................................................ 97
7.4.Text Commands for Size Functions.................................................................................................. 98
8. Meshing Objects and Material Points................................................................................................. 103
8.1. Objects......................................................................................................................................... 103
8.1.1. Object Attributes.................................................................................................................. 103
8.1.1.1. Approaches For Creating Objects................................................................................. 105
8.1.2. Object Based Meshing.......................................................................................................... 106
8.1.3. Using the Manage Objects Dialog Box.................................................................................. 107
8.1.3.1. Defining Objects.......................................................................................................... 107
8.1.3.2. Creating Multiple Objects............................................................................................ 108
8.1.3.3. Object Manipulation Operations.................................................................................. 108
8.1.3.4. Object Transformation Operations............................................................................... 109
8.1.3.5. Automatic Alignment of Objects.................................................................................. 110
8.1.4.Text Commands for Objects.................................................................................................. 110
8.2. Material Points.............................................................................................................................. 114
8.2.1. Using the Material Point Dialog Box...................................................................................... 117
8.2.2. Using Text Commands.......................................................................................................... 117
9. Manipulating the Boundary Mesh...................................................................................................... 119
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9.1. Manipulating Boundary Nodes...................................................................................................... 119
9.1.1. Free and Isolated Nodes....................................................................................................... 119
9.1.2.Text Commands for Manipulating Boundary Nodes............................................................... 120
9.2. Intersecting Boundary Zones........................................................................................................ 121
9.2.1. Intersecting Zones................................................................................................................ 121
9.2.2. Joining Zones....................................................................................................................... 122
9.2.3. Stitching Zones.................................................................................................................... 123
9.2.4. Using the Intersect Boundary Zones Dialog Box.................................................................... 125
9.2.5.Text Commands for Boundary Intersection............................................................................ 126
9.3. Modifying the Boundary Mesh...................................................................................................... 128
9.3.1. Using the Modify Boundary Dialog Box................................................................................. 128
9.3.2. Operations Performed: Modify Boundary Dialog Box............................................................. 128
9.3.3. Locally Remeshing a Boundary Zone or Faces....................................................................... 135
9.3.4.Text Commands for Boundary Modification.......................................................................... 135
9.4. Improving Boundary Surfaces....................................................................................................... 138
9.4.1. Improving the Boundary Surface Quality.............................................................................. 138
9.4.2. Smoothing the Boundary Surface......................................................................................... 138
9.4.3. Swapping Face Edges........................................................................................................... 138
9.4.4.Text Commands for Improving Boundary Surfaces................................................................ 139
9.5. Refining the Boundary Mesh......................................................................................................... 139
9.5.1. Procedure for Refining Boundary Zone(s).............................................................................. 139
9.5.2.Text Commands for Boundary Zone Refinement................................................................... 141
9.6. Creating and Modifying Features................................................................................................... 142
9.6.1. Creating Edge Loops............................................................................................................ 142
9.6.2. Modifying Edge Loops.......................................................................................................... 145
9.6.3. Using the Feature Modify Dialog Box.................................................................................... 146
9.6.4.Text Commands for Creating and Modifying Features............................................................ 148
9.7. Remeshing Boundary Zones.......................................................................................................... 149
9.7.1. Creating Edge Loops............................................................................................................ 150
9.7.2. Modifying Edge Loops.......................................................................................................... 150
9.7.3. Remeshing Boundary Face Zones......................................................................................... 150
9.7.4. Using the Surface Retriangulation Dialog Box....................................................................... 151
9.7.5.Text Commands for Remeshing............................................................................................ 152
9.8. Faceted Stitching of Boundary Zones............................................................................................ 154
9.9.Triangulating Boundary Zones....................................................................................................... 155
9.10. Separating Boundary Zones........................................................................................................ 155
9.10.1. Methods for Separating Face Zones.................................................................................... 155
9.10.2.Text Commands for Separating Face Zones......................................................................... 158
9.11. Projecting Boundary Zones......................................................................................................... 159
9.11.1.Text Commands for Projecting Boundary Zones.................................................................. 159
9.12. Creating Groups.......................................................................................................................... 159
9.12.1.Text Commands for User-Defined Groups............................................................................ 160
9.13. Manipulating Boundary Zones.................................................................................................... 161
9.13.1.Text Commands for Manipulating Boundary Zones............................................................. 161
9.14. Manipulating Boundary Conditions............................................................................................. 162
9.14.1.Text Commands for Manipulating Boundary Conditions...................................................... 163
9.15. Creating Surfaces........................................................................................................................ 163
9.15.1. Creating a Bounding Box.................................................................................................... 163
9.15.1.1. Using the Bounding Box Dialog Box........................................................................... 163
9.15.2. Creating a Planar Surface Mesh........................................................................................... 164
9.15.2.1. Using the Plane Surface Dialog Box............................................................................ 165
9.15.3. Creating a Cylinder/Frustum............................................................................................... 166
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9.15.3.1. Using the Cylinder Dialog Box.................................................................................... 168
9.15.4. Creating a Swept Surface.................................................................................................... 169
9.15.4.1. Using the Swept Surface Dialog Box........................................................................... 169
9.15.5. Creating a Revolved Surface............................................................................................... 170
9.15.5.1. Using the Revolved Surface Dialog Box....................................................................... 170
9.15.6. Creating Periodic Boundaries.............................................................................................. 171
9.15.7.Text Commands for Creating Surfaces................................................................................. 172
9.16. Additional Boundary Mesh Text Commands................................................................................. 172
10.Wrapping Boundaries....................................................................................................................... 177
10.1.The Wrapping Process................................................................................................................. 178
10.2. Examining and Repairing the Input Geometry............................................................................. 179
10.3. Initializing the Cartesian Grid....................................................................................................... 182
10.4. Examining the Cartesian Grid for Leakages.................................................................................. 186
10.4.1. Automatic Leak Detection.................................................................................................. 187
10.4.2. Manual Leak Detection....................................................................................................... 188
10.5. Extracting the Wrapper Surface................................................................................................... 191
10.6. Checking the Quality of the Wrapper Surface............................................................................... 194
10.7. Post Wrapping Improvement Operations..................................................................................... 195
10.7.1. Coarsening Options............................................................................................................ 195
10.7.2. Post Wrap Options.............................................................................................................. 196
10.7.3. Zone Options..................................................................................................................... 202
10.7.4. Expert Options................................................................................................................... 204
10.8.Text Commands for the Wrapper................................................................................................. 206
11. Creating a Mesh................................................................................................................................. 211
11.1. Choosing the Meshing Strategy................................................................................................... 211
11.1.1. Boundary Mesh Containing Only Triangular Faces............................................................... 212
11.1.2. Mixed Boundary Mesh........................................................................................................ 213
11.1.3. Hexcore Mesh .................................................................................................................... 214
11.1.4. CutCell Mesh...................................................................................................................... 214
11.1.5. Additional Meshing Tasks................................................................................................... 215
11.1.6. Inserting Isolated Nodes into a Tet Mesh............................................................................. 217
11.2. Using the Auto Mesh Dialog Box.................................................................................................. 219
11.2.1.Text Commands for Auto Mesh........................................................................................... 220
11.3. Generating Pyramids................................................................................................................... 220
11.3.1. Creating Pyramids.............................................................................................................. 221
11.3.2. Zones Created During Pyramid Generation......................................................................... 222
11.3.3.Text Commands for Generating Pyramids............................................................................ 223
11.3.4. Pyramid Meshing Problems................................................................................................ 223
11.4. Creating a Non-Conformal Interface............................................................................................ 225
11.4.1. Separating the Non-Conformal Interface Between Cell Zones.............................................. 225
11.4.2.Text Commands for Creating a Non-Conformal Interface..................................................... 226
11.5. Creating a Heat Exchanger Zone.................................................................................................. 226
11.6. Parallel Meshing.......................................................................................................................... 227
11.6.1.Text Commands ................................................................................................................. 228
12. Generating Prisms............................................................................................................................. 229
12.1. Overview.................................................................................................................................... 229
12.2. Procedure for Generating Prisms................................................................................................. 230
12.3. Prism Meshing Options............................................................................................................... 232
12.3.1. Growing Prisms Simultaneously from Multiple Zones.......................................................... 232
12.3.2. Growing Prisms on a Two-Sided Wall................................................................................... 234
12.3.3. Detecting Proximity and Collision....................................................................................... 235
12.3.4. Ignoring Invalid Normals.................................................................................................... 238
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12.3.5. Splitting Prism Layers......................................................................................................... 238
12.3.6. Preserving Orthogonality ................................................................................................... 239
12.4. Zones Created During Prism Generation...................................................................................... 239
12.5.The Prism Generation Process...................................................................................................... 240
12.6. Using Adjacent Zones as the Sides of Prisms................................................................................ 241
12.7. Direction Vectors......................................................................................................................... 244
12.8. Offset Distances.......................................................................................................................... 247
12.9. Improving Prism Quality.............................................................................................................. 249
12.9.1. Edge Swapping and Smoothing.......................................................................................... 249
12.9.2. Node Smoothing................................................................................................................ 250
12.9.3. Improving the Prism Quality............................................................................................... 250
12.9.4. Removing Poor Quality Cells............................................................................................... 251
12.9.5. Improving Warp ................................................................................................................. 252
12.10.Text Commands for Generating Prisms....................................................................................... 252
12.11. Prism Meshing Problems........................................................................................................... 261
13. Generating Thin Volume Mesh.......................................................................................................... 265
13.1. Overview.................................................................................................................................... 265
13.2. Procedure for Generating a Thin Volume Mesh............................................................................. 265
13.3.Text Command for Generating Thin Volume Mesh........................................................................ 266
14. Generating Tetrahedral Meshes........................................................................................................ 267
14.1. Automatically Creating a Tetrahedral Mesh.................................................................................. 267
14.1.1. Automatic Meshing Procedure for Tetrahedral Meshes........................................................ 267
14.1.2. Using the Auto Mesh Tool................................................................................................... 269
14.1.3. Automatic Meshing of Multiple Cell Zones.......................................................................... 269
14.1.4. Automatic Meshing for Hybrid Meshes................................................................................ 270
14.1.5. Further Mesh Improvements............................................................................................... 270
14.2. Manually Creating a Tetrahedral Mesh......................................................................................... 271
14.2.1. Manual Meshing Procedure for Tetrahedral Meshes............................................................. 271
14.3. Initializing the Tetrahedral Mesh.................................................................................................. 274
14.3.1. Using the Tet Dialog Box..................................................................................................... 274
14.3.2.Text Commands for Initializing the Mesh............................................................................. 275
14.4. Refining the Tetrahedral Mesh..................................................................................................... 276
14.4.1. Using Local Refinement Regions......................................................................................... 277
14.4.2. Using the Tet Dialog Box..................................................................................................... 278
14.4.3.Text Commands for Setting Refinement Controls................................................................. 279
14.5. Additional Text Commands for Tetrahedral Mesh Generation....................................................... 281
14.6. Common Tetrahedral Meshing Problems..................................................................................... 282
15. Generating the Hexcore Mesh........................................................................................................... 285
15.1. Hexcore Meshing Procedure........................................................................................................ 285
15.2. Using the Hexcore Dialog Box...................................................................................................... 286
15.3. Controlling Hexcore Parameters.................................................................................................. 287
15.3.1. Defining Hexcore Extents................................................................................................... 287
15.3.2. Hexcore to Selected Boundaries.......................................................................................... 288
15.3.3. Only Hexcore...................................................................................................................... 289
15.3.4. Maximum Cell Length......................................................................................................... 290
15.3.5. Buffer Layers ...................................................................................................................... 291
15.3.6. Peel Layers......................................................................................................................... 291
15.3.7. Local Refinement Regions.................................................................................................. 292
15.4.Text Commands for Hexcore Meshing.......................................................................................... 292
16. Generating the CutCell Mesh............................................................................................................ 295
16.1.The CutCell Meshing Process....................................................................................................... 295
16.2. Using the CutCell Dialog Box....................................................................................................... 300
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16.2.1. Handling Zero-Thickness Walls............................................................................................ 301
16.2.2. Handling Overlapping Surfaces.......................................................................................... 302
16.2.3. Resolving Thin Regions....................................................................................................... 303
16.3. Improving the CutCell Mesh........................................................................................................ 304
16.4. Post CutCell Mesh Generation Cleanup........................................................................................ 305
16.5. Generating Prisms for the CutCell Mesh....................................................................................... 305
16.6.The Cut-Tet Workflow.................................................................................................................. 309
16.7.Text Commands for CutCell Meshing........................................................................................... 311
17. Object-Based Meshing...................................................................................................................... 317
17.1. Object-Based Meshing Workflow................................................................................................. 317
17.1.1. Using the Mesh Generation Task Page................................................................................. 318
17.2. Preparing the Geometry.............................................................................................................. 319
17.2.1. Using a Bounding Box........................................................................................................ 320
17.2.2. Closing Annular Gaps in the Geometry................................................................................ 320
17.2.3. Creating Capping Surfaces.................................................................................................. 320
17.2.4. Defining Material Points..................................................................................................... 322
17.2.5. Defining Size Functions...................................................................................................... 323
17.2.6. Using User-Defined Groups................................................................................................ 323
17.3. Defining Objects......................................................................................................................... 323
17.4. Diagnostics................................................................................................................................. 323
17.4.1. Geometry Issues................................................................................................................. 324
17.4.2. Face Connectivity Issues..................................................................................................... 324
17.4.3. Quality Checking................................................................................................................ 325
17.5. Fixing Holes in Objects................................................................................................................ 325
17.6.Wrapping Objects....................................................................................................................... 327
17.6.1. Object Wrapping Options................................................................................................... 329
17.6.1.1.Wrapping Selected Objects........................................................................................ 329
17.6.1.2. Creating a New Wrap Object...................................................................................... 329
17.6.1.3. Resolving Thin Regions During Object Wrapping........................................................ 331
17.6.2. Repairing Wrap Objects...................................................................................................... 331
17.6.2.1. Detecting Holes in the Wrap Object............................................................................ 331
17.6.2.2. Removing Gaps Between Wrap Objects...................................................................... 331
17.6.2.3. Removing Thickness in Wrap Objects......................................................................... 333
17.6.2.4. Improving Feature Capture For Wrap Objects............................................................. 335
17.7. Sewing Objects........................................................................................................................... 335
17.7.1. Improving Wrap Objects..................................................................................................... 337
17.7.2. Resolving Thin Regions....................................................................................................... 337
17.7.3. Processing Slits................................................................................................................... 337
17.8. Improving the Mesh Objects....................................................................................................... 338
17.8.1. Removing Voids ................................................................................................................. 338
17.8.2. Improving Feature Capture For Mesh Objects...................................................................... 338
17.9. Build Topology............................................................................................................................ 338
17.9.1.Text commands for Build Topology..................................................................................... 341
17.10. Generating the Volume Mesh Based on Mesh Objects................................................................ 342
17.11.Text Commands for Object Based Meshing................................................................................ 343
18. Improving the Mesh.......................................................................................................................... 347
18.1. Smoothing Nodes....................................................................................................................... 347
18.1.1. Laplace Smoothing ............................................................................................................ 347
18.1.2.Variational Smoothing........................................................................................................ 348
18.1.3. Skewness-Based Smoothing............................................................................................... 348
18.1.4.Text Commands for Smoothing........................................................................................... 348
18.2. Swapping ................................................................................................................................... 349
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18.2.1.Text Commands for Swapping............................................................................................ 350
18.3. Improving the Mesh.................................................................................................................... 350
18.4. Removing Slivers from a Tetrahedral Mesh................................................................................... 350
18.4.1. Automatic Sliver Removal................................................................................................... 351
18.4.2. Removing Slivers Manually................................................................................................. 351
18.4.3.Text Commands for Sliver Removal..................................................................................... 352
18.5. Modifying Cells........................................................................................................................... 353
18.5.1. Using the Modify Cells Dialog Box....................................................................................... 353
18.5.2.Text Commands for Modifying Cell Zones............................................................................ 355
18.6. Moving Nodes ............................................................................................................................ 356
18.6.1. Automatic Correction......................................................................................................... 356
18.6.2. Semi-Automatic Correction ................................................................................................ 357
18.6.3. Repairing Negative Volume Cells......................................................................................... 358
18.6.4.Text Commands for Moving Nodes..................................................................................... 358
18.7. Cavity Remeshing....................................................................................................................... 358
18.7.1.Tetrahedral Cavity Remeshing............................................................................................. 359
18.7.2. Hexcore Cavity Remeshing................................................................................................. 361
18.7.3.Text Commands for Cavity Remeshing................................................................................ 363
18.8. Manipulating Cell Zones.............................................................................................................. 364
18.8.1. Active Zones and Cell Types................................................................................................ 364
18.8.2. Copying and Moving Cell Zones.......................................................................................... 364
18.8.3.Text Commands for Manipulating Cell Zones....................................................................... 365
18.9. Manipulating Cell Zone Conditions.............................................................................................. 368
18.9.1.Text Commands for Manipulating Cell Zone Conditions....................................................... 368
18.10. Using Domains to Group and Mesh Boundary Faces................................................................... 368
18.10.1. Using Domains................................................................................................................. 368
18.10.2. Defining Domains ............................................................................................................ 369
18.10.3.Text Commands for Domains............................................................................................ 369
18.11. Checking the Mesh................................................................................................................... 370
18.12. Checking the Mesh Quality........................................................................................................ 371
18.13. Clearing the Mesh..................................................................................................................... 371
19. Examining the Mesh.......................................................................................................................... 373
19.1. Displaying the Grid..................................................................................................................... 373
19.1.1. Generating the Grid Display Using the Display Grid Dialog Box............................................ 374
19.1.2. Grid Display Options........................................................................................................... 374
19.1.3.Text Commands for Displaying the Grid.............................................................................. 375
19.1.4.Text Commands for Grid Colors........................................................................................... 378
19.1.5.Text Commands for Style Attributes.................................................................................... 378
19.1.6. Displaying Objects ............................................................................................................. 379
19.1.6.1.Text Commands for Displaying Objects...................................................................... 379
19.2. Checking Face Distribution.......................................................................................................... 380
19.2.1.Text Commands for Face Distribution.................................................................................. 380
19.3. Checking Cell Distribution........................................................................................................... 380
19.3.1.Text Commands for Cell Distribution................................................................................... 380
19.4. Modifying the Attributes of the Plot Axes..................................................................................... 381
19.4.1.Text Commands for Modifying Axes Attributes.................................................................... 381
19.5. Controlling Display Options......................................................................................................... 381
19.5.1. Modifying the Display Options............................................................................................ 382
19.5.2.Text Commands for Controlling Display Options.................................................................. 383
19.6. Modifying the View..................................................................................................................... 386
19.6.1.Text Commands for Modifying the View.............................................................................. 386
19.7. Adding Lights............................................................................................................................. 387
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