[syavash]

Dear Foamers,

I just wanted to know that is this I that have problems with ICEM meshes when converting to foam or it is a general known issue. I cannot get a clean straight forward solution when importing ICEM meshes. No matter how much I try to improve mesh quality and aspect ratio, etc. I have generated very clean high-quality hexa meshes but OF always bothers me. I guess there are some issues related to numerical precision in the meshes generated in ICEM. I hope someone provide more insight, at least.

Thanks

[syavash]

Well, that is not a problem of ICEM .
I used another mesh from Gambit, very similar in terms of ratio and spacing to first ICEM one, and the same problem occurred.
The problem is in velocity field where non-physical reverse flow happens top and bottom of a 2-D circular cylinder, at Re=100 which I anticipate to be able to observe Karmann shedding. Reverse flow region is large initially and becomes smaller as I lower Courant No. It occurs near the separation point, so I guess I should still lower the cell aspect ratio in that region. Currently, I use a mesh with maximum AR of 15, but I am not sure how further I should lower mesh AR in that region.

Any comments is appreciated.

Thanks,
Syavash

[syavash]

I have provided two screen shots below, from velocity field, as well as an enlarged view of mesh, the small blue regions top and bottom of the cylinder represent reverse flow that should not be there actually.

Comment plz