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

[snappyHexMesh] snappyHexMesh - Poor surface

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 12, 2011, 07:08
Default snappyHexMesh - Poor surface
  #1
Member
 
Daniel
Join Date: Apr 2010
Location: Manchester
Posts: 30
Rep Power: 16
drrbradford is on a distinguished road
I'm trying to mesh an axisymmetric slender body (a finless missile) using snappyHexMesh. I have a very high quality .stl file and have modified the motorBike snappyHexMeshDict rather than write from scratch as I'm just getting to grips with openFoam. However, when I run sHM I get a very low quality surface as can be seen in the attached image for the first and second 'timestep' during sHM.

What I would like to know is which parameter in which Dict is it that controls the quality of the surface matching? I would be inclined to say that increasing the grid resolution in blockMeshDict would help. If this is so, is it possible to create a blockMesh cuboid around the missile geometry of high resolution which is contained within a larger domain cuboid? (See attached image)
Attached Images
File Type: png Domain_new.png (8.1 KB, 73 views)
File Type: png sHM.png (14.2 KB, 81 views)
Attached Files
File Type: txt blockMeshDict.txt (1.6 KB, 10 views)
drrbradford is offline   Reply With Quote

Old   August 12, 2011, 08:20
Default
  #2
Member
 
Daniel
Join Date: Apr 2010
Location: Manchester
Posts: 30
Rep Power: 16
drrbradford is on a distinguished road
OK, so it looks like I hadn't told sHMDict to refine the surface, only the refinement area.

Before I had:
Code:
 refinementRegions
    {
        refinementBox
        {
            mode inside;
	 levels ((0.5 1));
        }

    }
But now I have
Code:
 refinementRegions
    {
        refinementBox
        {
            mode inside;
	 levels ((0.5 1));
        }
motorBike
      {   mode distance;  
          levels ((0.0001 6) (0.001 5) (0.01 4) (0.1 3) (0.2 2));
      } 
    }
drrbradford is offline   Reply With Quote

Old   March 16, 2014, 12:43
Default
  #3
Senior Member
 
Sasan Ghomi
Join Date: Sep 2012
Location: Denmark
Posts: 292
Rep Power: 15
sasanghomi is on a distinguished road
Hi Daniel ,Have you solved the problem? Have you gotten a high quality surface? Actually I have a problem similar to you!!

Best regards,
Sasan.
sasanghomi 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
[CAD formats] Creating waterproof STL using snappyHexMesh or salome Tobi OpenFOAM Meshing & Mesh Conversion 58 May 13, 2020 07:01
[snappyHexMesh] Running snappyHexMesh in parallel - optimizing peterhess OpenFOAM Meshing & Mesh Conversion 2 January 3, 2018 03:54
[snappyHexMesh] Tutorial crashes: snappyHexMesh floating point exception. jasv OpenFOAM Meshing & Mesh Conversion 4 May 10, 2016 03:55
[snappyHexMesh] snappyhexmesh doesn't creat mesh in parallel issue? klausb OpenFOAM Meshing & Mesh Conversion 1 March 7, 2015 12:55
[snappyHexMesh] stitchMesh and snappyHexMesh gdbaldw OpenFOAM Meshing & Mesh Conversion 0 December 23, 2009 03:09


All times are GMT -4. The time now is 11:20.