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2013 ANSYS, Inc. February 13, 2014 1 ANSYS Confidential & Proprietary Information
Fluent Meshing: R15 Update
Vivek Patil.
ANSYS India
2013 ANSYS, Inc. February 13, 2014 2 ANSYS Confidential & Proprietary Information
Fluent Meshing at R15
Faceted Geometry
/CFD Mesh
CFD Volume
mesh
Surface & Prism
mesh
Build Topology or Wrap
Hole fixing Gap
closing
Diagnostics
Tool
Common Fluent GUI
Meshing toolbox
Fast Graphics
Improved part management
Improved Performance
Mesh
STL
Complex
CAD
CFX
Solver
Fluent
Solver
2013 ANSYS, Inc. February 13, 2014 3 ANSYS Confidential & Proprietary Information
Fluent Meshing R15
Outline Cad Import
Size Function
Graphics tools
GUI and Display
Diagnostics
Wrapping/Surface meshing
Volume Meshing
2013 ANSYS, Inc. February 13, 2014 4 ANSYS Confidential & Proprietary Information
R15 Cad import improvements
GUI changes and MB-part handling New initial GUI The Length unit moved to main panel
NOTE that length units are not preserved inside the Fluent solver
New Option GUI Object Granularity
For multi-body part import, a new option has been added, where you get one object per body, and one zone per CAD face
This sub option is not available for part and file selections
Downstream operations has also been adjusted for better handling of multi-body-part import
2013 ANSYS, Inc. February 13, 2014 5 ANSYS Confidential & Proprietary Information
R15 Cad import improvements
Conformal tessellation improvements Ability to save the size field created When using conformal tessellation, a size function
field is created.
Optionally this field can be saved and reused The file extension .sf is automatically recognized
It is recommended to always include the length unit in the Size Field name Ex. cad-file-name-mm.sf
After the FS field is saved, the field is also directly accessible for any future SF driven operation within the current session Wrap, remesh, sew, etc.
Ability to read in a size field during CAD import Make sure that the size field are consistent with the
length units used
2013 ANSYS, Inc. February 13, 2014 6 ANSYS Confidential & Proprietary Information
R15.0 Cad import graphics
Different defaults after CAD import After importing a new mesh or Stl file, many default settings needs to be
changed to get a nice looking model
But during CAD-import, many display options are automatically modified Colours are by ID and turned on
Edges are turned off
Face displacement are set to 1
Animation option is set to ALL
Head light is on
Mesh import R15 CAD import
2013 ANSYS, Inc. February 13, 2014 7 ANSYS Confidential & Proprietary Information
R15 Size Function improvements
Size Function Scaling Using a simple scale factor
you can quickly re-mesh faces, solids or the full connected CFD model with different mesh densities
Original mesh density
Scale = 1.5
Scale = 0.7
2013 ANSYS, Inc. February 13, 2014 8 ANSYS Confidential & Proprietary Information
R15 Size Function improvements
New workflow for advanced conformal mesh import Import CAD file using default tessellation For very large CAD files, save in PMDB format for quicker consecutive imports
Assign size function controls and compute the Size Field Verify the size distribution using probes (ctrl-y) or/and contours
Save the Size Field Re-import CAD or saved PMDB file and use saved size function
2013 ANSYS, Inc. February 13, 2014 9 ANSYS Confidential & Proprietary Information
Fluent Meshing R15
Outline Cad Import
Size Function
Graphics tools
GUI and Display
Diagnostics
Wrapping/Surface meshing
Volume Meshing
2013 ANSYS, Inc. February 13, 2014 10 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools
10-20 times faster graphics speed than R14.5
Many new short-cuts for increased productivity All Short-cuts can be accessed on screen using Ctrl-h
All main short-cuts are also displayed in the transcript window Secondary short-cut options are displayed in the corner of the display window
2013 ANSYS, Inc. February 13, 2014 11 ANSYS Confidential & Proprietary Information
R15.0 Graphics tools - Display
2) Select and Hide again: Ctrl-shift-h
Pick this Object: Ctrl-b
3) Undo (Ctrl-Shift-u ) twice or Show all (Ctrl-Shift a) 1) Hide: Ctrl-Shift-h
Hide all other (Isolate): Ctrl-Shift-i
Some Examples.
2013 ANSYS, Inc. February 13, 2014 12 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools - Display
New display short cuts (Toggles) Ctrl-shift-e: Show/Hide the mesh (edges) on selected or all zones/object
Ctrl-shift-t: Make zones/objects transparent/opaque
Select this zone/object
2013 ANSYS, Inc. February 13, 2014 13 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools - Display
New display short cuts (Toggles) Ctrl-Shift-x: Change to exploded
/imploded view of objects/zones
Ctrl-Shift-z: Restrict to Edge-zone, -edge and -node selection mode
(Ctrl-e) + Select edges on edge zones
(Ctrl-n) + Select nodes on edge zones
(Ctrl-z) + Select edge zones
2013 ANSYS, Inc. February 13, 2014 14 ANSYS Confidential & Proprietary Information
Ctrl-shift-d + Ctrl-s: Display only Zones/Objects with similar surface area
R15.0 Graphics Tools - Display
Pick this Zone/Object
New display mode shortcuts Change to conditional display mode : Ctrl-shift-d
Ctrl-shift-d + Ctrl-n: Display only neigbouring Zones/Objects
2013 ANSYS, Inc. February 13, 2014 15 ANSYS Confidential & Proprietary Information
Ctrl:c Display only entities with similar surface curvature/radius
R15.0 Graphics Tools - Display
Pick this Zone/Object
New display mode shortcuts Change to conditional display mode : Ctrl-shift-d
Ctrl-Shift-a
2013 ANSYS, Inc. February 13, 2014 16 ANSYS Confidential & Proprietary Information
R15 Graphics tools Zone Management
Separate by seed (40) (Ctrl-Shift-s) Transperent view
Separate by angle (40) (Ctrl-Shift-S) Select one zone(Ctrl-Z)
Select one face(Ctrl-F)
Separation using shortcuts
2013 ANSYS, Inc. February 13, 2014 17 ANSYS Confidential & Proprietary Information
R15 Graphics tools Zone Management
Select faces (Ctrl-f)
Select Target Zone (Ctrl-z) and Set (Ctrl-s)
Separate by seed (40) (Ctrl-Shift-s)
Select source Face (or Edge) and project (Ctrl-p)
Local Gap closing using shortcuts
2013 ANSYS, Inc. February 13, 2014 18 ANSYS Confidential & Proprietary Information
R15 Graphics tools Zone Management
Select this zone(Ctrl-z) and Set (Ctrl-S)
Select this zone
Mark will indicate the source and target faces where the gap will close
Issue Ctrl-k will open this panel
Remove closes the gap
Global gap closing using shortcuts
2013 ANSYS, Inc. February 13, 2014 19 ANSYS Confidential & Proprietary Information
R15 Graphics tools Zone Management
Use (Ctrl-shift- g) and select 3 nodes on the corners, to create a local coordinate system for the source object F5
Select 3 nodes on the corners, to create a local coordinate system for the target object F5
1
2
3
1
2
3
Select the source object to align. Apply align with F5
Aligning two rectangular objects using shortcuts
2013 ANSYS, Inc. February 13, 2014 20 ANSYS Confidential & Proprietary Information
R15 Graphics tools Zone Management
Use (Ctrl-shift- g) and select 6 nodes, 3 nodes on each circle, to create a local coordinate system for the source object F5
Select 6 nodes, 3 nodes on each circle, to create a local coordinate system for the target object F5
Select the source object to align A preview indicates the new position. Apply align with F5
Aligning two circular bodies using shortcuts
2013 ANSYS, Inc. February 13, 2014 21 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools Zone Management
New construct mode shortcuts After the loop has been traced
Use Ctrl-l for edge loop creation
Use Ctrl-k for capping
2013 ANSYS, Inc. February 13, 2014 22 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools - Meshing
Some Examples.
Ctrl-shft-f: Feature imprint of a wrapper surface Select the Edge zone for imprint and the corresponding Face zones
If only Faces are picked, rezone will be executed
2013 ANSYS, Inc. February 13, 2014 23 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools Meshing
Remesh using shortcuts Remeshing (Ctrl-shift-r) locally around face triangles
Indicating the number of rings around the selected triangle to be remeshed
Using the local size of the remesh boundary or Size Function
2013 ANSYS, Inc. February 13, 2014 24 ANSYS Confidential & Proprietary Information
R15.0 Graphics Tools - Meshing
Conformal, multi-zone re-meshing using shortcuts Pick one or several face zones Issue Ctrl-Shift-r
A size function field needs to be available
2013 ANSYS, Inc. February 13, 2014 25 ANSYS Confidential & Proprietary Information
Fluent Meshing R15
Outline Cad Import
Size Function
Graphics tools
GUI and Display
Diagnostics
Wrapping/Surface meshing
Volume Meshing
2013 ANSYS, Inc. February 13, 2014 26 ANSYS Confidential & Proprietary Information
R15 GUI enhancements
Number of children
Hierarchical list view Creates an compress view depending on a entity name separation symbol
Expand/compress toggle by picking the name and issuing Ctrl-LMB The expansion works on multiple levels if the same symbol appears multiple
times in the entity name
The separation symbol (period by default) can be changed on the main panel In the compressed mode, the number of children and
the number of selected children are indicated
Number of selected children
2013 ANSYS, Inc. February 13, 2014 27 ANSYS Confidential & Proprietary Information
R15 GUI enhancements
Mesh Generation panel changes Objects panel Draw, List, Delete
Object type
Manage Objects panel The List tab has been removed Toggles to list all zones and selected
object zones are instead available
Wrapping individual objects replaces the original object with the corresponding wrapped object
Ability to select and draw relevant (original) faces and edges of a wrap or sew object
Purge Wrap removes the wrap object and reinstates the original object
2013 ANSYS, Inc. February 13, 2014 28 ANSYS Confidential & Proprietary Information
R15 GUI enhancements
New Object Transformation Tab was added Rotate using Pivot and Axis Optionally use Define which is enabling the new graphical local coordinate
system to define rotation pivot and axis
Scale Translate
Optionally use Define to define a translation vector using two positions or nodes
2013 ANSYS, Inc. February 13, 2014 29 ANSYS Confidential & Proprietary Information
R15 GUI enhancements
New Revolve Surface creation tool
Revolve an edge around an arbitrary axis
Number of segments for mesh density Angle (up to 360 degrees) Scale factor (for local offsetting)
Example
Ctrl-e to pick an edge and Ctrl-shift-s to Separate an edge zone
Select the edge zone Fill in appropriate angle, scale
and interval parameters
Define (using LCS) or specify an axis and pivot
Create
Scale = 1.1
Scale = 1.0
Edge Zone
2013 ANSYS, Inc. February 13, 2014 30 ANSYS Confidential & Proprietary Information
R15 GUI/TUI enhancements
Miscellaneous Better Material Point Management Create, Draw, Delete, List, etc.
Display Grid - Cells All option replaced with Bounded to
avoid displaying all cells
TUI for STL export Colour by normal Optional object creation for Swept, Revolved and Planar surface creation
Define a local vector using nodes/points In Swept surface and Periodic panel
Easier selection in dual panels Merge nodes, Thin Volume, etc.
Pick zone on screen and press Graphics Select to transfer the selection to respective panel
2013 ANSYS, Inc. February 13, 2014 31 ANSYS Confidential & Proprietary Information
R15 Display/View enhancements
Clipping planes Bounds using clip-planes Avoids re-draw (faster)
Good for cross sectional view
Insert clipping planes Faster and easier
Flip direction option
Display options Moved to the top Mesh Edge toggle added
Scene Overlay now available in main panel
2013 ANSYS, Inc. February 13, 2014 32 ANSYS Confidential & Proprietary Information
Fluent Meshing R15
Outline
R15 Enhancements Cad Import
Size Function
Graphics tools
GUI and Display
Diagnostics
Wrapping/Surface meshing
Volume Meshing
Beta Features
2013 ANSYS, Inc. February 13, 2014 33 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Diagnostics are a central in finding problems, prior to volume meshing
Diagnostics is divided into three sections Geometry
Find and fix assembly problems
Gaps or intersections between objects
Face connectivity
Ensure surface mesh validity
Free or multi-edges, overlapping/intersecting faces, etc.
Quality
Improve surface mesh quality
Using combinations of criteria
2013 ANSYS, Inc. February 13, 2014 34 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Diagnostics workflow Select objects
Mark Marks and provides a number of unvisited
problem areas
First Displays only the objects with the issue
containing most number of effected triangles
Reset Resets the number of unvisited
Summary Gives a brief summary of some potential
problems
object-name free multi- duplicate skewed(> 0.85) max-skew face-zones edge-zones -------------------- ------------ ------------ ------------------ ------------------------- ------------------ ------------ summary 0 0 0 312 0.99999524 32 32
2013 ANSYS, Inc. February 13, 2014 35 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Remove Gaps between objects Set Min, Max and Proximity gap
Mark and click on First
Remove for Current opens Remove Gaps
Parameters are populated
Just Click Remove
Click on Next.
2013 ANSYS, Inc. February 13, 2014 36 ANSYS Confidential & Proprietary Information
R15 Diagnostics Self Face Proximity To find Gaps and acute angles
within an object
Preferably use graphics tools to close gaps
Use Remove for Current with caution since the boundary of the mesh can be very uneven and faces may collapse
A fillet is created to avoid the problem
Acute angle can create bad feature capturing after wrapper
Final mesh after wrapping
2013 ANSYS, Inc. February 13, 2014 37 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Geometry: Find Intersections With Self and Cross intersections, you can find out where you have intersections
in your model
You can create intersection loop for All or Current intersection location
2013 ANSYS, Inc. February 13, 2014 38 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Face Connectivity : Free nodes You have three operations possible for eliminating free nodes
Node Merge:
Absolute or relative tolerance
Stitch:
Includes steps to gradually stitch free nodes with neighbouring nodes with increase tolerance
Delete:
Free edges, with 1, 2 or 3 free sides
Fringes
Delete Fringes
Faceted Stitch
2013 ANSYS, Inc. February 13, 2014 39 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Face Connectivity : Multi-connected nodes There are several fix options for multi-connected
Delete Fringes:
Essentially the same operation as in Free nodes
Delete overlaps
Both overlapping and multi-connected
Disconnect:
Separate two faces that has been connected
2013 ANSYS, Inc. February 13, 2014 40 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Face Connectivity : Self-intersection Self intersection fixes includes
Fix self intersection (moving boundaries apart)
Fix folded faces
Fix Folded (also fix self intersection)
Smoothing
Folded face Self intersection
2013 ANSYS, Inc. February 13, 2014 41 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Face Connectivity : Self-proximity Important for cases where Multibody parts
were only partly created
Self proximity fixes includes
Find acute face-face angles
Find and close gaps using Ctrl-k
Small gaps
Acute face-face angles
2013 ANSYS, Inc. February 13, 2014 42 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Face Connectivity : Non-manifold Non manifold is used to remove point-contact situations
Prisms has to be applied on the boundary zones to activate this operation and to find the problem
Fix by Removing the point contact and smoothing the nodes
2013 ANSYS, Inc. February 13, 2014 43 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Face Connectivity : Leaks My model looks multi-connected and I have
no free nodes, but still it does not mesh?
Maybe there is a leak?
Insert a clipping plane to access inside faces
Pick one face (Ctrl-f) on the inside and one on the outside
Trace leak using Ctrl-t
Leak found
2013 ANSYS, Inc. February 13, 2014 44 ANSYS Confidential & Proprietary Information
R15 Diagnostics
Surface Quality You can mark faces based on multiple quality criteria
Skewness level of 0.7 or better is recommended for good quality prism layers
Four different resolutions methods exist
General improve
Face Collapse
Smooth
Swap
Recommended approach
Use Face collapse and/or general improve with gradually increasing angle (30, 60, 90)
Apply All
Remove the Preserve boundary option and fix locally for the final bad quality cells
Collapse was able to resolve all bad cells
2013 ANSYS, Inc. February 13, 2014 45 ANSYS Confidential & Proprietary Information
R15 Repair tools
Fix Holes Combines auto-hole identification with
automatic tracing Select objects
Set fluid material point (wetting point)
For each range of sizes (based on computed Size Field ) Issue find holes
Set target material point (external )
For each trace Select hole
Patch hole
Open all remaining holes
Verify wetted surface
Optionally shrink wrap
2013 ANSYS, Inc. February 13, 2014 46 ANSYS Confidential & Proprietary Information
Fluent Meshing R15
Outline
R15 Enhancements Cad Import
Size Function
Graphics tools
GUI and Display
Diagnostics
Wrapping/Surface meshing
Volume Meshing
2013 ANSYS, Inc. February 13, 2014 47 ANSYS Confidential & Proprietary Information
R15 Wrapper
Three different shrink-wrap options For different speed and surface recovery/Quality Low (initial/raw wrapper surface)
Fast, without imprinting
Used to verify size density, identify cross-overs, etc.
Medium (Traditional wrapper)
Same as shrink-wrap at R14.5
Suitable for very dirty geometries, surface patches etc.
High (New re-meshed wrapper)
Faster, more accurate feature capturing and better quality compared to traditional wrapper
Find cross-overs with low wrap Change Size Function and properly resolve with high wrap
2013 ANSYS, Inc. February 13, 2014 48 ANSYS Confidential & Proprietary Information
R15 Wrapper
Original
Low: Quick&Dirty
Medium + Improve: Max Skew ; .98 High: Max Skew ; .64
2013 ANSYS, Inc. February 13, 2014 49 ANSYS Confidential & Proprietary Information
R15 Wrapper
High Wrap options Impact on resolution factor with edge proximity set to 2 cells per gap
Resolution factor wraps with a size function that is scaled by 0.75, and the re-meshes with the actual size function
Find cross-overs with low wrap
Resolved with resolution factor of 0.75 Cross-overs with resolution factor of 1
2013 ANSYS, Inc. February 13, 2014 50 ANSYS Confidential & Proprietary Information
R15 Build Topology
Build Topology supports several workflows Use Join and Intersect to create a multi-body part from an Assembly
This makes use of the already existing conformal tessellation
Multi-body-part import from CAD or from a External surface mesh Alternative Domain creation and Cell type verification
Lets look at an example (Burner Assembly) to see the workflow Before Build topology Cad import using conformal faceting Ensure that no free nodes exist (Diagnostics)
Close gaps Use Cross proximity in Diagnostics
Close inlets/outlets/holes
Create a Material point for the Fluid volume
Change all objects to type Wrap
2013 ANSYS, Inc. February 13, 2014 51 ANSYS Confidential & Proprietary Information
R15 Build Topology
Build Topology workflow Use intersect to connect baffles and
imported capping faces to the rest of the model Optionally use Find Pairs to verify that the
appropriate triangles on the capping faces are included marked
Often for caps/baffles, a tolerance of 0.1 needs to be used
Marked Faces to be joined
Marked Faces to be intersected
Conformal cap
2013 ANSYS, Inc. February 13, 2014 52 ANSYS Confidential & Proprietary Information
R15 Build Topology
Build Topology workflow Use Diagnostics to Make sure that no Free nodes, Self intersection or Duplicate
faces exists after the Build Topology operation
In this case, 20 free nodes were found Remove fringes (All) resolves 18 of them
Stitch (Current) with a high tolerance resolves the last 2
2013 ANSYS, Inc. February 13, 2014 53 ANSYS Confidential & Proprietary Information
R15 Build Topology
Build Topology workflow In Diagnostics; Check Self intersections
including the Folds option
Mark; 250 locations are found
Use the Fix Folded Faces option
Apply for All
Mark again All self-intersections are resolved
In Diagnostics; Summary No more free or Duplicate faces
2013 ANSYS, Inc. February 13, 2014 54 ANSYS Confidential & Proprietary Information
R15 Build Topology
Build Topology workflow Prepare for Auto mesh When all the connectivity problems are resolved,
the topology can be created
Click on the Region tab
Select all Face zones
Select Material points
Compute
This will create the list of regions that corresponds to the cell zones that will be created during AutoMesh
Verify Regions by selecting the fluid region
The corresponding face zones are highlighted
The Name and Type are correctly identified
2013 ANSYS, Inc. February 13, 2014 55 ANSYS Confidential & Proprietary Information
R15.0 Re-meshing strategy
Surface re-meshing is very powerful at R15 Re-meshing often improves quality and reduces surface mesh size after
conformal import, wrapper or build topology Remesh is patch-independent within zones
CAD import with Conformal tessellation is always CAD-face patch conforming
Wrapper need each gap to be resolved by 2-3 times smaller than the actual gap distance to avoid cross over
Wrapped face are often refined due to sources outside of the wrapped boundary
Removal of steps in Diagnostics results in no source of proximity
Closing and joining gaps will also remove sources of proximity
Scaling or recalculating Size Function? If sources of refinement has been removed,
recalculation is recommended Note that new features need to be extracted
out if edge driven size function is needed
Marked faces with skew over 0.5 before and after remesh
Import with conformal faceting
2013 ANSYS, Inc. February 13, 2014 56 ANSYS Confidential & Proprietary Information
R15 Surface re-meshing
Use GUI for more feature controls
Boundary Mesh - Remesh Select features to preserve !
In Face Remesh options include
Size Function
Replace Face
Use conformal remesh
Remeshing using Ctrl-Shift-r
Remeshing using GUI
Feature Ignored
Feature Preserved
2013 ANSYS, Inc. February 13, 2014 57 ANSYS Confidential & Proprietary Information
Fluent Meshing R15
Outline
R15 Enhancements Cad Import
Size Function
Graphics tools
GUI and Display
Diagnostics
Wrapping/Surface meshing
Volume Meshing
2013 ANSYS, Inc. February 13, 2014 58 ANSYS Confidential & Proprietary Information
R15 Volume Meshing
Thin Volume Meshing
Supporting Conformal mesh across adjacent domains
Multiple sources
Multiple layers
T-junctions
collapsed side faces, etc.
2013 ANSYS, Inc. February 13, 2014 59 ANSYS Confidential & Proprietary Information
R15 Volume Meshing
Thin Volume Meshing
Procedure Select Source face(s)
Select Target face
Graphics Select available
Max Gap thickness
If 0 is used, the thickness will be calculated
Number of divisions
Growth rate
From Source to Target
Normally, the source mesh is kept, while the target is replaced by the cap of the source
When Remesh Overlap Zones is un-ticked a non-conformal setup is needed
2013 ANSYS, Inc. February 13, 2014 60 ANSYS Confidential & Proprietary Information
Prism layers
Faster growth via layer splitting Division of prime number of layers are
also supported
2-3x speed-up for 5-15 layers
R15 Prism Layer splitting
Initial Final
2013 ANSYS, Inc. February 13, 2014 61 ANSYS Confidential & Proprietary Information
Prism layers
Post layer splitting also supported Option to change growth rate based on total height
R15 Prism Layer Splitting
2013 ANSYS, Inc. February 13, 2014 62 ANSYS Confidential & Proprietary Information
R15 Prism Controls
Post ignore and post smooth accessible from Prisms Ability to include advanced prism post improve tools
as part of Prism setup (and hence Automesh) procedure
These were only accessible as post operations in R14.5
2013 ANSYS, Inc. February 13, 2014 63 ANSYS Confidential & Proprietary Information
R15 Volume Meshing
HexCore Meshing
~10-30% overall speed-up HexCore only (without tet): ~50% speed-up
0
0.5
1
UTM(sedan)
EA(truck)
EA(armature)
LandingGear
Alternator
HexCore ONLY Speed-Up (Normalized)
14.5
15.0
2013 ANSYS, Inc. February 13, 2014 64 ANSYS Confidential & Proprietary Information
R15 Volume Meshing
Tet Meshing using Size Function
Access to body of influence refinement (BOI) Prism+ tet meshing of a generic car using two BOIs
BOI created by scaling the surface mesh
BOI generated with bounding box creation
2013 ANSYS, Inc. February 13, 2014 65 ANSYS Confidential & Proprietary Information
R15 Distributed Parallel tet-prism
Starting Fluent Meshing in Parallel Mode Setting both number of Meshing and Solver
nodes. Meshing nodes =< meshing domains
Distributed Parallel meshing Only Prism + Tet meshing are supported
Connected and surface meshed decompositions should be created in advance
Use Build topology panel to assign the correct Fluid/Solid/Dead cell regions for the partitions
Open the Parallel panel Compute Partitions
- Identifies each topology region
- Each region (Compute Node Num) can be drawn for verification
Distribute Mesh
- Distributes each region to respective node
- Note that many TGrid options are unavailable
2013 ANSYS, Inc. February 13, 2014 66 ANSYS Confidential & Proprietary Information
R15 Distributed Parallel tet-prism
Parallel Meshing (cont.) Supported Prism and tet meshing tools in Parallel
Prism Smooth & Improve
Prism (Post) ignore
Auto-node-move
The mesh stays distributed when switching to solver mode
Agglomerate mesh
This command should be avoided since puts the mesh back on a single node and defeats the purpose of parallel meshing (both speed and memory)
2013 ANSYS, Inc. February 13, 2014 67 ANSYS Confidential & Proprietary Information
R15 Volume mesh performance
Distributed Parallel Tet-Prism meshing
Results for conformal identical pre-decomposed domains 42.5 million cells on 16 CPUs
Direct parallel transfer to Fluent solver after meshing
1
2 4
8
16
1 1.8
3.7
7.4
10.8
Spe
ed
up
CPU
Parallel meshing speedup factor
Ideal
Automesh
0
2000
4000
6000
8000
10000
12000
14000
16000
0 5 10 15 20
Peak memory per CPU
Meshed
Ideal