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Old   June 27, 2011, 16:33
Default Check case help
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J. Robbins
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hey guys im getting this error for check case..

"maximum cell skewness is greater than 0.98. consider improving the mesh quality before proceeding with your simulation."

also in the text window
"skewness exceeded 0.98 at 15 cells on thread ID = 3.Skewness exceeded 0.98 at 15 cells on thread ID = 3."

can anyone explain:
-What it cell skewness is?
-if this is causing in major errors in the caculations?
-and possible solutoins.

thanks!
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Old   June 28, 2011, 01:23
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Maxime Perelli
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your mesh contains cells with poor quality.
http://my.fit.edu/itresources/manual...equiangle_skew

Fix this issue by modifiying topology (merge,split, etc...) and/or remeshing
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Old   June 30, 2011, 10:21
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Adrien Lemoine
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A simulation with cell skewness greater than 0.98 will run but will give awful results such as acceleration of the flow in the middle of nowhere.

You should thing about remeshing the surface mesh (surface skewness < 0.5 will help you to have a cell skewness < 0.9), or using tools such as auto node move (in Tgrid 3d)

Adrien

Btw, to have good results the cell skewness should be less than 0.9 at least
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Old   June 30, 2011, 11:55
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Thanks for the help, im using workbench to generate my mesh. What are there imputs that are variable to limit the skewness?
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Old   June 30, 2011, 16:43
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Sorry, can't help you with workbench. I never used it, but you have to make your triangular mesh as equilateral as possible and then the cell skewness will be good too
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