ANSYS Meshing User's Guide PDF

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ANSYS Meshing User's Guide ANSYS, Inc. Release 15.0 Southpointe November 2013 275 Technology Drive Canonsburg, PA 15317 ANSYS, Inc. is [email protected] certified to ISO 9001:2008. http://www.ansys.com (T) 724-746-3304 (F) 724-514-9494 Copyright and Trademark Information © 2013 SAS IP, Inc. Al...

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ANSYS Meshing User's Guide

ANSYS, Inc. Southpointe 275 Technology Drive Canonsburg, PA 15317 [email protected] http://www.ansys.com (T) 724-746-3304 (F) 724-514-9494

Release 15.0 November 2013 ANSYS, Inc. is certified to ISO 9001:2008.

Copyright and Trademark Information © 2013 SAS IP, Inc. All rights reserved. Unauthorized use, distribution or duplication is prohibited. ANSYS, ANSYS Workbench, Ansoft, AUTODYN, EKM, Engineering Knowledge Manager, CFX, FLUENT, HFSS and any and all ANSYS, Inc. brand, product, service and feature names, logos and slogans are registered trademarks or trademarks of ANSYS, Inc. or its subsidiaries in the United States or other countries. ICEM CFD is a trademark used by ANSYS, Inc. under license. CFX is a trademark of Sony Corporation in Japan. All other brand, product, service and feature names or trademarks are the property of their respective owners.

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Table of Contents Capabilities in ANSYS Workbench .............................................................................................................. 1 Meshing Overview ................................................................................................................................. 1 Meshing Implementation in ANSYS Workbench ...................................................................................... 1 Types of Meshing ................................................................................................................................... 2 Assembly Level Meshing vs. Part/Body Level Meshing ........................................................................ 2 Meshing by Algorithm ...................................................................................................................... 2 Meshing by Element Shape ............................................................................................................... 4 Conformal Meshing Between Parts ......................................................................................................... 5 Usage in Workbench ................................................................................................................................. 11 Basic Meshing Application Workflows ................................................................................................... 11 Overview of the Meshing Process in ANSYS Workbench ................................................................... 11 Overview of the Meshing Process for CFD/Fluids Analyses ............................................................... 12 Combining CFD/Fluids Meshing and Structural Meshing ................................................................. 14 Strategies for CFD/Fluids Meshing in ANSYS Workbench ........................................................................ 15 Accessing Meshing Functionality .......................................................................................................... 17 Overview of the Meshing Application Interface ..................................................................................... 18 Determination of Physics, Analysis, and Solver Settings .......................................................................... 20 Working with Legacy Mesh Data ........................................................................................................... 21 Exporting Meshes or Faceted Geometry ................................................................................................ 23 Mesh Application File Export ........................................................................................................... 24 Fluent Mesh Export ......................................................................................................................... 24 Classes of Zone Types in ANSYS Fluent ...................................................................................... 26 Standard Naming Conventions for Naming Named Selections ................................................... 29 Zone Type Assignment ............................................................................................................. 30 Examples of Fluent Mesh Export: An Alternative to Using a Fluid Flow (Fluent) Analysis System .......................................................................................................................................... 35 Polyflow Export .............................................................................................................................. 42 CGNS Export ................................................................................................................................... 43 ANSYS ICEM CFD Export ................................................................................................................. 44 Exporting Faceted Geometry to TGrid (ANSYS Fluent Meshing) ........................................................ 53 Extended ANSYS ICEM CFD Meshing ..................................................................................................... 55 Writing ANSYS ICEM CFD Files ......................................................................................................... 56 Rules for Interactive Editing ............................................................................................................ 58 Limitations of ANSYS ICEM CFD Interactive ...................................................................................... 58 Working with Meshing Application Parameters ..................................................................................... 58 ANSYS Workbench and Mechanical APDL Application Meshing Differences ........................................... 59 Mesh Controls Overview ........................................................................................................................... 61 Global and Local Mesh Controls ............................................................................................................ 61 Understanding the Influence of the Advanced Size Function ................................................................. 61 Global Mesh Controls ............................................................................................................................... 65 Defaults Group ..................................................................................................................................... 65 Physics Preference .......................................................................................................................... 65 Solver Preference ............................................................................................................................ 67 Relevance ....................................................................................................................................... 67 Sizing Group ......................................................................................................................................... 67 Use Advanced Size Function ........................................................................................................... 68 Curvature Size Function ............................................................................................................ 69 Proximity Size Function ............................................................................................................. 70 Fixed Size Function ................................................................................................................... 71 Specifying Size Function Options .............................................................................................. 71 Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information of ANSYS, Inc. and its subsidiaries and affiliates.

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Meshing User's Guide Curvature Normal Angle ..................................................................................................... 72 Num Cells Across Gap ......................................................................................................... 72 Proximity Size Function Sources .......................................................................................... 72 Min Size ............................................................................................................................. 74 Proximity Min Size .............................................................................................................. 75 Max Face Size ..................................................................................................................... 75 Max Size ............................................................................................................................. 76 Growth Rate ....................................................................................................................... 76 Relevance Center ............................................................................................................................ 76 Element Size ................................................................................................................................... 77 Initial Size Seed ............................................................................................................................... 77 Smoothing ..................................................................................................................................... 77 Transition ....................................................................................................................................... 78 Span Angle Center .......................................................................................................................... 78 Minimum Edge Length ................................................................................................................... 78 Inflation Group ..................................................................................................................................... 78 Use Automatic Inflation .................................................................................................................. 80 None ........................................................................................................................................ 80 Program Controlled .................................................................................................................. 81 All Faces in Chosen Named Selection ........................................................................................ 82 Inflation Option .............................................................................................................................. 83 Transition Ratio .............................................................................................................................. 85 Maximum Layers ............................................................................................................................ 85 Growth Rate ................................................................................................................................... 86 Number of Layers ........................................................................................................................... 86 Maximum Thickness ....................................................................................................................... 86 First Layer Height ............................................................................................................................ 86 First Aspect Ratio ............................................................................................................................ 86 Aspect Ratio (Base/Height) .............................................................................................................. 86 Inflation Algorithm ......................................................................................................................... 87 View Advanced Options .................................................................................................................. 90 Collision Avoidance .................................................................................................................. 90 Fix First Layer ...................................................................................................................... 94 Gap Factor .......................................................................................................................... 94 Maximum Height over Base ...................................................................................................... 94 Growth Rate Type ..................................................................................................................... 94 Maximum Angle ....................................................................................................................... 95 Fillet Ratio ................................................................................................................................ 95 Use Post Smoothing ................................................................................................................. 96 Smoothing Iterations ................................................................................................................ 97 Assembly Meshing Group of Controls .................................................................................................... 97 Method .......................................................................................................................................... 97 Feature Capture .............................................................................................................................. 98 Tessellation Refinement .................................................................................................................. 98 Intersection Feature Creation .......................................................................................................... 99 Morphing Frequency ...................................................................................................................... 99 Keep Solid Mesh ............................................................................................................................. 99 Patch Conforming Options Group ....................................................................................................... 100 Triangle Surface Mesher ................................................................................................................ 100 Patch Independent Options ................................................................................................................ 101 Topology Checking ....................................................................................................................... 102 Advanced Group ................................................................................................................................. 104

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Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information of ANSYS, Inc. and its subsidiaries and affiliates.

Meshing User's Guide Number of CPUs for Parallel Part Meshing ..................................................................................... 104 Shape Checking ............................................................................................................................ 104 Element Midside Nodes ................................................................................................................ 106 Straight Sided Elements ................................................................................................................ 107 Number of Retries ......................................................................................................................... 107 Extra Retries For Assembly ............................................................................................................ 108 Rigid Body Behavior ...................................................................................................................... 108 Mesh Morphing ............................................................................................................................ 108 Defeaturing Group .............................................................................................................................. 109 Pinch ............................................................................................................................................ 109 Pinch Control Automation Overview ....................................................................................... 112 How to Define Pinch Control Automation ................................................................................ 116 How to Define or Change Pinch Controls Manually .................................................................. 117 Usage Information for Pinch Controls ...................................................................................... 117 Loop Removal ............................................................................................................................... 119 Automatic Mesh Based Defeaturing .............................................................................................. 120 Statistics Group .................................................................................................................................. 121 Nodes ........................................................................................................................................... 121 Elements ...................................................................................................................................... 121 Mesh Metric ................................................................................................................................. 122 Element Quality ...................................................................................................................... 127 Aspect Ratio Calculation for Triangles ...................................................................................... 128 Aspect Ratio Calculation for Quadrilaterals ............................................................................. 129 Jacobian Ratio ........................................................................................................................ 130 Warping Factor ...................................................................................................................... 132 Parallel Deviation ............................................................................