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Old   December 14, 2012, 11:16
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hallo, right now i simulate a Fan-modell and i just want to finish the grid independence study. but i dont know if i must do the same improvement for the prism layer and the core mesh. Or i just need do it for the core mesh.
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Old   December 14, 2012, 21:22
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When you keep the prism layer thickness the same, you will end up with cells with bad aspect ratios. When you don't keep the prism layer thickness, you will end up with a different mesh topology. So there's no "right" solution.
Anyway, I would adjust the prism layer thickness to make a good mesh. Your prism layers should be reasonable in terms of number of layers and transition to the core mesh, then it shouldn't harm to change all by the same factor.
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Old   December 17, 2012, 12:01
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thanks for your advice. the same words i have told my tutor. but he asks anyhow for the reasons- why i dont or do improve the qualtiy of prism layer. could you just tell me where i can find some literature that i can quote as evidence or what.

Last edited by sydrna; December 17, 2012 at 12:05. Reason: doubled
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Old   December 17, 2012, 12:04
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Quote:
Originally Posted by abdul099 View Post
When you keep the prism layer thickness the same, you will end up with cells with bad aspect ratios. When you don't keep the prism layer thickness, you will end up with a different mesh topology. So there's no "right" solution.
Anyway, I would adjust the prism layer thickness to make a good mesh. Your prism layers should be reasonable in terms of number of layers and transition to the core mesh, then it shouldn't harm to change all by the same factor.
thanks for your advice. the same words i have told my tutor. but he asks anyhow for the reasons- why i dont or do improve the qualtiy of prism layer. could you just tell me where i can find some literature that i can quote as evidence or what
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