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-   -   mesh quality (http://www.cfd-online.com/Forums/ansys-meshing/91241-mesh-quality.html)

prince_pahariaa August 4, 2011 07:08

mesh quality
 
what is the acceptable range of quality of mesh in gambit ?? can it be generalize for every case ??

-mAx- August 4, 2011 09:13

it depends on your mesh (hexa, tetra, etc...)
I would say 0.9 for tetra and 0.8 for hexa.
But you can export a mesh which skewness doesn't exceed 0.97.
In every case, you may run a check mesh in your solver.
Running a model, which mesh quality is about 0.95 doesn't necessary means that you will have problem (peaks in Residuals, or exotic solution). But it is possible

prince_pahariaa August 5, 2011 01:52

Thanks max..

I was getting mesh qulaity of around .25-.30 if i use tetra mesh.. and around .79 if i use hexa..

I am getting entirely different results if i only change the mesh type. with tetra mesh my mass flux is balanced and i am getting some realistic output. But with hexa mesh mass flux itself not balanced. I have changed nothing in boundary condition or anything except mesh type (from tetra to hexa mesh)..

Do u have any idea where the problem may be.. ??

Once again thanks a lot..

-mAx- August 5, 2011 01:56

Without more information, it is quite difficult to evaluate the situation.
What are you modeling? Post picture of your mesh with tetra and hexa

prince_pahariaa August 8, 2011 02:53

1 Attachment(s)
Hey max

i guess i found out what problem is. I checked the grid in fluent and found unexpected wall in my geometry which is hindering the flow. Might be if i remove that wall, i will get my solution.

I really appreciate your help.

-mAx- August 8, 2011 02:56

unwanted walls may come from not-connected surfaces.
>> Surfaces / Connect / All


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