CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Meshing & Mesh Conversion

[snappyHexMesh] Understanding feature edge refinement and snapping

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   May 31, 2012, 06:11
Lightbulb Understanding feature edge refinement and snapping
  #1
Member
 
Florian
Join Date: Nov 2009
Posts: 59
Rep Power: 16
Horus is on a distinguished road
Hello,

I'm in the process of meshing a 1:4 vehicle aerodynamics wind tunnel with snappyHexMesh. Input files are a bunch of STLs, OF is 2.1.0, solver will be simpleFoam.

The complete snapyHexMeshDict is available at http://pastebin.com/a71XxWHF Any comments welcome!

Using SHM I still have some trouble understanding the feature edge refinement and snapping.

In my snappyHexMeshDict I have resolveFeatureAngle 140. I understand that this creates an edge mesh (same like surfaceFeatureExtract -includedAngle 140).

  1. refinementSurfaces
  2. {
  3. GEOM_windTunnel.stl
  4. { level (5 6); }
  5. }
This edge mesh is used for refinement (to level 6) when cells are intersected by the edge. Is this correct?

Now there is the parameter nFeatureSnapIter 10 which tries to align faces to the features. Does it use the features that are caught by resolveFeatureAngle or does it need to have an edge mesh file given in the features () dict?

I tried it with and without nFeatureSnapIter 10. Both meshes were visually almost identical but the mesh with nFeatureSnapIter enabled was much worse when it came to checkMesh quality measures. Number of cells was around 27M.

Thanks for help & any comments!

Florian
Horus is offline   Reply With Quote

Old   May 31, 2012, 12:08
Default
  #2
Senior Member
 
lore
Join Date: Mar 2010
Location: Italy
Posts: 460
Rep Power: 18
lovecraft22 is on a distinguished road
Send a message via Skype™ to lovecraft22
You need to run surfaceFeatureExtract first the use the emesh files generated to mesh the edges.

Have a look at this discussion here:
http://www.cfd-online.com/Forums/ope...ture-edge.html
lovecraft22 is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
decomposePar problem: Cell 0contains face labels out of range vaina74 OpenFOAM Pre-Processing 37 July 20, 2020 05:38
[snappyHexMesh] No satisfying result with feature edge refinement Krapf OpenFOAM Meshing & Mesh Conversion 5 December 13, 2019 06:59
[snappyHexMesh] Error snappyhexmesh - Multiple outside loops avinashjagdale OpenFOAM Meshing & Mesh Conversion 53 March 8, 2019 09:42
[snappyHexMesh] Edge Refinement fracasce OpenFOAM Meshing & Mesh Conversion 3 December 2, 2017 13:30
[snappyHexMesh] Weird snapping outside a refinement region jasimpson89 OpenFOAM Meshing & Mesh Conversion 0 July 29, 2012 20:46


All times are GMT -4. The time now is 04:48.