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-   -   [ANSYS Meshing] Negative Cell Volumes (http://www.cfd-online.com/Forums/ansys-meshing/89479-negative-cell-volumes.html)

donkey86 June 14, 2011 04:05

Negative Cell Volumes
 
Hi there!

I am still trying to mesh a pipe with a radial inlet. Running quality checks
I get negative cell volumes on most of the edges. I tried adapting the spacing and ratio values but still no improvement. The associations of edges and vertices look fine as far as I know. Can somebody help me please?

donkey86 June 14, 2011 04:09

1 Attachment(s)
there you have a screenshot

user_of_cfx June 14, 2011 06:33

I can't see the cross-section very well, are you using an O grid? It seems that where the inlet is the mesh gets unusually distorted, or maybe it's the angle with which I'm looking at it. Usually an O-grid will solve most of the problems near the edges. If the distortion I see is where the negative quality elements are, then this is a tell-tale sign that an O-grid is needed.

If you do have an O-grid and still get this, how did you create your geometry? Sometimes trying a different approach to get the same geometry solves some problems.

Hope it helps.

donkey86 June 16, 2011 02:26

thanks for your help, I tweaked the geometry and solved my problems. now there is a smal amount of cells left, but I i am hopefull to get rid of them soon.


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