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O-grid generation unsuccessful

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Old   March 30, 2010, 18:35
Default O-grid generation unsuccessful
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Jialin Su
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I created a single block to fit a 3D wing and tried generate O-grid around the block. But it ended up with a warning saying that generation of O-grid is not successful and I could not proceed with the mesh generation. Has anyone encountered something similar and could anyone provide advice on that? Thanks.
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Old   March 31, 2010, 01:35
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Hello,

How did you try to create the o-grid?
Have you tried the tutorial on the wing body?

regards
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Old   March 31, 2010, 09:57
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Right, Ogrid is very robust, but you need to pick it correctly... Try the tutorial first and then get back to your wing...
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Old   April 5, 2010, 11:37
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Dear all,
I always can't be succeful with O grid.
in ICEM have no problem, but when imported into fluent, always diverge, so I doult my O grid have problem. This is the first time I use O grid, who can give me some suggestions ?

My model is not complicated, one building in an rectangular domain, I want to generate an O grid around the building.

my method is seclecting the block and a face, and then associate the internal O block vertics with the building geometry.
Who can give me some suggestions, what I should pay attation to when using O gird , if I should associate edges or orther face with geometry ?
Thank you very much.
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Old   April 6, 2010, 03:15
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Hi,

From your screen shots, I think that mesh is good. Could you check the mesh quality and errors in ICEM CFD? If fluent reads your mesh and passed the grid check, then mesh has no errors. I think that some solver set up may be causing the divergence. So recheck once again the sover set up.

Hope this will help U
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Old   April 6, 2010, 03:22
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One more thing. Are doing mesh for building also? Did you define the two domains (one for building and another one for outer area) in ICEM CFD. In fluent, just check there are two domains or not.

If you defined correctly or you are not modeling the building (you already deleted the block inside building in ICEM CFD), just ignore this reply.
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Old   April 7, 2010, 10:25
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Dear JSM,
Thank you very much.You are right, the grid have no problem. Because OpenFOAM can simulation. So I check fluent solver set again.
When I decrease the under-relaxation factors, doesn't use the defalt value, the simulation can going on. But when you use regular tectangular mesh, using default set is OK.

This is mesh quanlity.
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