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Problems on Tetrahedra to Polyhedra using polyDualMesh on concave surface object

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Old   July 23, 2008, 12:38
Default I'd like to using OpenFOAM wit
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Martin/Run DU
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I'd like to using OpenFOAM with polyhedra mesh to simulate a flow field in a pipe connected volume, like the image:

I use salome to generate this mesh with netgen(1d-2d-3d)

I have set up the boundaries as independent as each surface is a boundary, then convert it to polyhedra using polyDualMesh, but checkMesh said that there are several concave faces and wrong oriented faces:



the black colored faces is concave faces which are just around the connection edge of the two near boundaries.

However, I set some surfaces together as one boundaries including the neighbor surfaces with concave angle. I can converted it to polyhedra without errors, but the original edge between the concave surfaces becomes to several faces with polygon, so it loses the geometry information.



My problem is: how to convert tetra to polymesh avoiding concave faces without losing geometric infomation like such volume?

Thank you in advance.

Martin/Run Du
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Old   July 7, 2009, 02:19
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Björn Fabritius
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Hello Martin,
I just recently read your post. Did you by now find a solution to your problem? 'Cause I'm having trouble with the same effect as you describe above.

Regards,
Bjoern
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Old   July 18, 2009, 12:58
Default trick with polyDualMesh
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Quote:
Originally Posted by bfa View Post
Hello Martin,
I just recently read your post. Did you by now find a solution to your problem? 'Cause I'm having trouble with the same effect as you describe above.

Regards,
Bjoern

Hi ! I had exactly the same problem when using polyDualMesh, ie a loss of the geometrical informations... but I found a trick to avoid this problem : I use a mesh made of only one patch, then I use polyDualMesh with 0 angle, and finaly I divide the single patch with autoPatch. Now I have a good shape for my dual mesh... but I have a new problem using refineWallLayer. For some surfaces mesh I got the following message :
"achorpoints and nonanchorpoints are geometrically on same side!" Do you have an idea to solve this problem ? Does it come from the original mesh ?
Sincerely,
JB
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