Lecture 1:
Introduction
14.5 Release
Introduction to ANSYS
Fluent Meshing
© 2011 ANSYS, Inc.
December 21,
2012
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Day 1
Morning
Lecture 1 – Introduction to Fluent Meshing
Lecture 2 – Fundamentals of Fluent Meshing and the User Interface
Demo
Lecture 3 – Boundary Meshing Tools
Workshop 1 – Basic Skills (ASMO geometry)
Afternoon
Lecture 4 – Volume Fill Methods
Workshop 2 – Volume Fill Method (Sedan geometry)
Lecture 5 – CutCell Meshing
Workshop 3 – Cutcell Meshing (Manifold geometry)
© 2011 ANSYS, Inc.
December 21,
2012
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Day 2
Morning
Lecture 6 – CAD Import
Workshop 4 – CAD Import (Exhaust geometry)
Lecture 7 – Workflow Basics
Afternoon
Lecture 8 – Wrapping, Fixing and Sewing
Workshop 5 – Basic Workflows (T-Junction geometry)
Lecture 9 – Advanced Topics and Tips
Workshop 6 – CAD import and Tessellation (Pipe geometry)
© 2011 ANSYS, Inc.
December 21,
2012
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Introduction to ANSYS Fluent Meshing
Fluent Meshing overview and Characteristics
Meshing Overview
• Boundary mesh modification/improvement
• Surface mesh generation methods
• Volume mesh generation methods
Summary
© 2011 ANSYS, Inc.
December 21,
2012
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Who Uses Fluent Meshing?
Courtesy of Lola Cars
•
The majority of long-standing Fluent Meshing (legacy TGrid) users
are in the aerospace and automotive markets, including F1.
•
Fluent Meshing can create very high quality, large cell count,
hybrid volume meshes for external aerodynamics.
•
Such users create a high quality surface mesh externally and use
Fluent Meshing for volume mesh growth.
© 2011 ANSYS, Inc.
December 21,
2012
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But it’s also great for...
Courtesy of John Deere
Courtesy of Materialise
Courtesy of Lilleaker Consulting AS
and Inocean-Marotec AS
• The other area of growth in use of Fluent Meshing is in the
utilisation of it’s
technology
• Often used in HVAC, Oil & Gas, Biomedical or underhood thermal
management where
• Starting point is faceted/STL geometry or CAD
• Geometry can be “dirty” with disconnected surfaces,
overlapping geometry, surface intersections, holes etc.
© 2011 ANSYS, Inc.
December 21,
2012
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Fluent Meshing Characteristics
Advanced Meshing
• Based on the TGrid Meshing Tool
• All TGrid Functionality embedded into the Fluent User Interface
at Release 14.5
• Enhancements made at R14.5 to read CAD and also surface
mesh complex multi-region assemblies
• Geared towards advanced users with a lot of control
– “Transparent box” not “black box”
• Can handle billion cell+ meshes
• Includes direct nodal control of mesh
• Text User Interface
– Used for scripting and batch execution
Courtesy of Lola Cars
© 2011 ANSYS, Inc.
December 21,
2012
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Fluent Meshing “Traditional Workflow”
Fluent Meshing is a High-fidelity Meshing tool
Prior to Release 14.5, two main approaches were used:
1. Large applications, starting from High quality Surface Mesh
– Often used in combination with GAMBIT/ANSA/ICEM CFD/Ansys Meshing
– Prism Layer Creation
– Tets / HexCore Meshing
2. Starting from Low quality Faceted/STL geometry
– Wrapper for cleanup, simplification, connectivity and surface mesh generation
• Wrapper Size Function based
• Manual and Automatic hole detection and fixing
• Feature recovery
• Resolving overlapping/self-intersecting surfaces
• Surface mesh quality improvement tools
• Volume meshing
– Alternatively use Cutcell for top-down surface and volume meshing in one shot
© 2011 ANSYS, Inc.
December 21,
2012
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Fluent Meshing “Object Based Workflow”
•
At R14.5 new functionality allows users to create high fidelity
surface meshes inside Fluent Meshing with an entirely new
workflow
•
New surface meshing options include:
• Direct conformal faceting on CAD import for single fluid volumes
• Surface wrapping using Advanced Size Functions by:
• Shrink-Wrap (pure nodal-projection algorithm)
• Cut-Wrap (cell decomposition and nodal-projection algorithm)
• Sew option to combine separate surface meshes into a single, conformal
surface mesh for multi-region meshing. Required for e.g. Conjugate Heat
Transfer (CHT) studies
•
DAY1 of the Fluent Meshing Training Course will concentrate
on the “Traditional Workflow”
•
DAY2 will focus on the “Object Based Workflow” and the
CAD readerDecember
options
© 2011 ANSYS, Inc.
21,
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2012
Traditional and Object-Based Workflows
Traditional Workflow
The two workflows
have many functions
in common and once
they are well
understood users can
use combinations
•
For simplicity of
teaching the
Traditional Workflow
is explained first on
DAY1 and then the
Object-Based
Workflow is on DAY2
© 2011 ANSYS, Inc.
December 21,
2012
Object-Based Workflow
•
This split also allows TGrid literate trainees
to attend only DAY2 for an update on
Object-Based workflows only
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Repair Boundary Mesh
Plot and report mesh
quality
Connect, intersect or join
surface meshes
© 2011 ANSYS, Inc.
December 21,
2012
Display Cut-Planes
Separate, merge and
group zones
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Display/fix highly skewed
faces/cells
Project nodes to
feature lines – full
local control
Mesh Generation Methods
Surface
Wrapping
Tet
Meshing
Prism
Meshing
Hexcore
Meshing
Cutcell
Meshing
Pyramid
Meshing
© 2011 ANSYS, Inc.
December 21,
2012
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Some Caveats...
• Certain operations in Fluent Meshing
cannot be undone
– Merge nodes
– Delete Face Zones
– Imprinting of prisms onto adjacent tri
boundaries
– ...
We therefore advise saving meshes
incrementally as you work!
© 2011 ANSYS, Inc.
December 21,
2012
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Summary
•
Fluent Meshing is a robust and powerful mesh generation
software for unstructured meshing
•
Fluent Meshing contains several tools:
– To handle, repair and improve boundary meshes
– Surface Wrapping capabilities that can be used to generate CFD meshes on
highly complex and “dirty” geometry
– Class leading prism mesh generation capabilities allowing the capture of
boundary layers on complex geometry
– High quality tetrahedral and hexcore meshing algorithms
– Cutcell mesh which create both surface and hex-dominant volume mesh at the
same time
– Scripted meshing for repeatability and capture of best practices
•
Deep toolbox of commands available to tweak meshes generated
to user requirements and locally fix problem areas without full
remesh – a “transparent meshing toolbox”
© 2011 ANSYS, Inc.
December 21,
2012
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