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[ANSYS Meshing] Difference between average skewness and maximum skewness

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Old   February 14, 2018, 10:32
Default Difference between average skewness and maximum skewness
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Hello, I am trying to simulate a 2D, unsymmetrical airfoil and i am using unstructured mesh. The following are the skewness values of my mesh:

1. Min Skewness: 3.015* e-07
2. Max Skewness: 0.94216
3. Average Skewness: 6.54*e-02
4. Standard Deviation: 9.4*e-02

The standard deviation and average skewness are very less while maximum skewness is very high.

What should be the deciding parameter before proceeding to solve? Average skewness? or Maximum Skewness? Does this depend on things like physics of the flow, location of this max skewed element, etc ? If so, how?

Thank you
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Old   February 14, 2018, 13:44
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Maximum Skeweness is what you should be keeping an eye out for. The solvers in ANSYS(fluent,cfx) is very capable of handling bad meshes.

However, i must say that a bad skew element will effect your solution and convergence (stability) (thus the physics of the solution). So its good to improve the skewness and (orthogonality, aspect ratio and minimum angle) as much as you can before you take the mesh to solver.


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Old   February 15, 2018, 04:47
Default Way to reduce skewness
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Thank you sir for the reply

Is there a way in Ansys Meshing, or Fluent, to reduce the skewness of a few selective elements?
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Old   February 15, 2018, 05:34
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Quote:
Originally Posted by ParasuRam View Post
Thank you sir for the reply

Is there a way in Ansys Meshing, or Fluent, to reduce the skewness of a few selective elements?
ofcourse. if you show the problematic area with pictures a lot of people on this forum will help
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Old   February 15, 2018, 06:22
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Unlike in ICEM, smoothing in ANSYS Meshing is applied to the entire mesh and up until R19 it was only defined by choosing one option from three in a drop down list. If you want much greater control in making and editing a mesh move to ICEM.
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