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1 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
16.0 Release
Lecture 3:
Introduction to ANSYS Meshing
Introduction to ANSYS Meshing
2 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Introduction to ANSYS Meshing
In this lecture we will learn:
• Process for pre-processing using ANSYS tools
• What is the ANSYS Meshing?
• Meshing Fundamentals
• How to launch ANSYS Meshing?
• ANSYS Meshing interface
• Geometry concepts
• Meshing methods
3 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Preprocessing Workflow
Sketches and Planes
Geometry Import Options
3D Operations
Bi-Directional
CAD/ Neutral
Geometry Cleanup and Repair
Automatic
Cleanup
Simplification,
Mid-surface,
Fluid Extraction
Extrude, Revolve,
Sweep, etc
3D Operations
Booleans,
Decompose, etc.
Import/ Geometry Creation
Geometry Modifications
Meshing Solver
Meshing Methods
Hybrid Mesh: Tet,
Prisms, Pyramids
Hexa Dominant,
Sweep meshing
Global Mesh Settings
Local Mesh Settings
Sizing, Controls,
etc.
Assembly
Meshing
4 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
What is ANSYS Meshing
ANSYS Meshing is a component of ANSYS Workbench
• Meshing platform
• Combines and builds on strengths of preprocessing offerings from ANSYS:
– ICEM CFD, TGRID (Fluent Meshing), CFX-Mesh, Gambit
Able to adapt and create Meshes for different Physics and Solvers
• CFD: Fluent, CFX and POLYFLOW
• Mechanical: Explicit dynamics, Implicit
• Electromagnetic
Integrates directly with other WB systems
5 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Meshing Fundamentals
Purpose of the Mesh
• Equations are solved at cell/nodal locations
– Domain is required to be divided into discrete cells (meshed)
Mesh Requirements
• Efficiency & Accuracy
– Refine (smaller cells) for high solution gradients and fine geometric detail.
– Coarse mesh (larger cells) elsewhere.
• Quality
– Solution accuracy & stability deteriorates as mesh cells deviate from ideal shape
6 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Meshing Process in Ansys Meshing
• Physics, Sizing, Inflation, Pinch, …
• Sizing, Refine, Pinch, Inflation, …
• Preview surface mesh, Inflation
• Mesh metrics, Charts
7 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Launching ANSYS Meshing
• ANSYS Meshing is launched within Workbench
– 2 ways :
Fluid Flow (Fluent), Fluid Flow (CFX),
From Analysis Systems
Mesh
From Component Systems
Double click Mesh in the
System
or right click and select Edit
8 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Graphics User Interface
Mesh Metrics
Graphics window
Section Planes
Manage views
Details view
Outline
Toolbars
Units Bar Entity Details Bar
Message window
Worksheet
9 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Outline
Three default sections
• Geometry
– Bodies
• Coordinate Systems
– Default global & user defined systems
• Mesh
– Meshing operations (controls & methods)
displayed in the order in which they are inserted
In the tree
• Right clicking on any object
– launches a context sensitive menu
– Example: contains commands to generate, preview, clear mesh etc.
10 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Details View
Accessing Object Details
• Select an object (in the Outline)
– Related information to that object are displayed in the Details View below
– Ex: Select a body (“Fluid”) in the Outline
Details of “Fluid” : contains graphical and geometric details
– To access meshing details
Click the Mesh object or any of the inserted objects
• The Details View provides options to
– review,
– edit or
– input
values for every object in the Tree
11 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Geometry Configuration – Multiple Parts
• Geometry composed of Multiple parts
– No connection between parts (no face sharing)
‘Contact Region’ is automatically created between 2 faces
Each part meshed independently
Results in Non-conformal interface. Meshes do not match. No nodes connection.
Independent faces
Grid interface - Fluent
GGI - CFX
12 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Geometry Configuration – Multi-body Parts
• Geometry composed of multiple bodies in a part
– Depend on ‘Shared Topology method’ (in DM)
None o Results in a none connection between the bodies (similar to multiple parts)
Automatic
Faces in contact imprinted & fused Form a single face shared between the 2 bodies
Results in Conformal mesh
Common face acts as ‘Interior’
13 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Geometry Configuration – Multiple – body Parts
• Geometry composed of multiple bodies in a part
Imprints
Faces are imprinted on each other ‘like’ faces
Contact Region is automatically created
non conformal interface
For identical mesh on these faces, use ‘Match Control’ Results in unconnected mesh
Grid interface - Fluent
GGI - CFX
14 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Meshing – 3D Geometry
• 3D cell Types
• First Meshing Approach
Part/Body based • Meshing occurs at part or
body level. • Meshing Methods are scoped
to individual bodies. • Method assignment can be
automatic or manual. • Bodies contained in one part
are conformally meshed.
Part/Body Methods • Tetrahedrons.
− Tetras only
• Sweep. − Prisms & hexahedrons
• MultiZone. − Mainly hexahedron
• Hex Dominant − Not for CFD
• Automatic. − Sweep + PC Tet
(Depends on bodies) or PC Tet
15 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Meshing – 3D Geometry
• Second Meshing Approach
Cut Cell Meshing Assembly Meshing • Meshes an entire model in one
process. − Assembly of parts
• Performs boolean operations. − Volume filling, intersection &
combination − Does not require prior fluid body
definition or shared topology.
• Conformal mesh created across parts.
Assembly Meshing
Methods • Generate mainly
− Hexahedrons − Tetrahedrons
Part/Body Meshing & Assembly Meshing
not interoperable
16 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Summary
What have we learnt in this session:
• The global process to run ANSYS Meshing
• On overview of the interface and
• The various Geometry configurations
– Multiple parts
– Multi-body parts
– Multiple body parts
• Meshing methods
– Part/body based
– Assembly meshing
And the associated
shared topology option
17 © 2015 ANSYS, Inc. February 12, 2015 ANSYS Confidential
Workshop 3.1 – Ansys WB Meshing Basics