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Old   February 9, 2008, 00:38
Default Maximum Mesh Expansion Factor
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Hi, The solver output gives the following message under 'Mesh Statistics'. ************************************************** *** Minimum Orthogonality Angle [degrees] 30.0 ok Maximum Aspect Ratio = 20.1 OK

Maximum Mesh Expansion Factor = 118.8 ! ************************************************** ******

What does the sign of '!' mean besides the 'Maximum Mesh Expansion Factor'? Please help.

Thanks, KK

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Old   February 9, 2008, 00:47
Default Some more information to my problem
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Just one more comment... I checked Edge length ratio and it was less than 10. And I use inflation and the first layer thickness is set to be 1 mm while the maximum element size is 2.5 mm. At a few places I have used spacing to start with 1 mm.
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Old   February 10, 2008, 17:31
Default Re: Some more information to my problem
Glenn Horrocks
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The ! means that the value is high and has a significant chance of causing a convergence or accuracy problem. If possible you should try to improve the mesh to reduce the number.

It is normally OK to have quite high aspect ratio elements in the boundary layer against a surface, providing they are prism or hexa elements.

Glenn Horrocks
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Old   February 11, 2008, 06:12
Default Re: Some more information to my problem
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Hai KK,

The Maximimum Mesh Expansion Factor just reflects that in your mesh the cells does not expand in an orderly manner. If you are working with ICEM, then check for the elements with higher Volume Change value and try to bring their value down, near to 20. This could be easily done by just changing the edge length raio.

Pre-Mesh params -> Meshing parameters -> Edge params


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