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checkmesh failed

dear all,

I am simulating flow around cylinders recently. I added some rings around the cylinder which looks like the picture below. However, it seems there's something wrong with the mesh because this message bumps out when i run checkMesh:

Code:

 Mesh non-orthogonality Max: 180 average: 17.0344

 ***Number of non-orthogonality errors: 27720.

  <<Writing 27720 non-orthogonal faces to set nonOrthoFaces

also, some values like Cd and Cl produced by the simulation are far from correct.

I believe the non-orthogonality of the mesh happens in the region where the ring is placed, as is shown in the second picture. Is there any strategy of meshing to avoid this kind of problem? BTW I'm using gmsh as the mesh generator.

thanks in advance!

Hi,

I'm not sure how you can avoid the non-orthogonal faces. But if you want to locate them, you can run the command

Code:

foamToVTK -faceSet nonOrthoFaces

You can then visualize the non orthogonal faces in ParaView and understand where they come from.

Regards,
Eloïse

Thanks for your help! !
It helped me to locate the bad meshes, although i still can not figure out where the problem is:confused::confused:

Quote:

Originally Posted by Eloise (Post 446921)

Hi,

I'm not sure how you can avoid the non-orthogonal faces. But if you want to locate them, you can run the command

Code:

foamToVTK -faceSet nonOrthoFaces

You can then visualize the non orthogonal faces in ParaView and understand where they come from.

Regards,
Eloïse