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abhinit December 28, 2006 11:49

TGRID- Problem in generating Viscous Mesh

I am using TGRID 3.6.8 I am generating Viscous Hybrid Mesh (Prism + Tet) over my surface mesh.

I have surface mesh with maximum skewnees at 0.61 (0.50-0.60 12 cells out of 200K + faces)

I have divided my geometry in 8 zones and grown Prism layer over 6 zones. It is difficult to grow prism layers on other 2 zones as it leads to negative volume, probably due to prims colliding with each other.

So I am growing tet mesh over these 2 zones and my prism cap.

All goes well and it succesfuly meshes all nodes. But just before climax.. It gives a Error " No Cell Zones", and my tet mesh fails.. I tried lot of permutation and combination but in vain. Somebody who knows solution to this problem PLEASE HELP ITS URGENT...

Emily January 4, 2007 16:05

Re: i have the same problem, please help me!!! *NM*

Pino January 8, 2007 06:37

Re: TGRID- Problem in generating Viscous Mesh

probably you hav not selected in the right way te faces for the tet-domain. You must pay attention to include prism-cap and prism-side and to exclude the 6 faces on which you extruded the boundary layer

abhinit January 8, 2007 09:48

Re: i have the same problem, please help me!!!
Hi Emily, Pino

Happy New Year!

I solved my problem and I m glad to share with you.

TGRID gives 'NO CELLS FOUND' error when there is some 'HOLE' is mesh, means there may be some face which are not meshed.

Now in my case during prism creation, there are two surfaces are created one tri-surface with name prism-cap and other quad surface with name prism-side.

Now when we are creating Tet mesh, it can be grown only on Tri-surfaces, so there are all quad surfces lying unmeshed and therefore are HOLES in our mesh.

The solution is to create Pyramid cells over these quad surfaces and then create tet cells.

You can refer TGRID Manual , section 7.4.4, 'Creating prism `cells'.

If you still have problem, please do write, I will be more than happy to help you out.

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