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-   -   Dynamic meshing of oscillating airfoil (2d) (http://www.cfd-online.com/Forums/fluent/121639-dynamic-meshing-oscillating-airfoil-2d.html)

abhiramBA August 2, 2013 01:19

Dynamic meshing of oscillating airfoil (2d)
 
Hello,
I am trying to simulate the oscillatory motion of an airfoil. I have successfully compiled my udf and the library is also loaded. I do not know what settings I should use in the dynamic mesh. Only the airfoil seems to oscillate and the grid stays as it is. :confused:
Also, when I solve, I get an error saying "Update-Dynamic-Mesh failed. Negative cell volume detected."
Kindly guide me through the dynamic meshing.

hy2049 August 6, 2013 22:50

Hi, I'm doing the same thing with you. I also met some problems. So would you like to share your files with me and let's figure out the problems together.

abhiramBA August 7, 2013 01:41

1 Attachment(s)
Alright!
Here is my grid.

vasava August 7, 2013 03:05

'Negative cell volume' error indicates that you haven't done the 'dynamic mesh' settings properly.

Can you post your settings here? It would help to help.

vasava August 7, 2013 03:11

More over...
1. The mesh/boundary displacement per time step can not be more that the smallest element size of your mesh.
2. The mesh/boundary displacement per time step should be selected so that the minimum quality of the mesh (after update) does not exceed the worst quality of the mesh you have declared.

hy2049 August 7, 2013 03:31

Quote:

Originally Posted by abhiramBA (Post 444254)
Alright!
Here is my grid.

Is that better to use an unstructure mesh if we want to use dynamic mesh here?

vasava August 7, 2013 05:38

Quote:

Originally Posted by hy2049 (Post 444281)
Is that better to use an unstructure mesh if we want to use dynamic mesh here?

Yes indeed. Using triangular mesh elements would be more appropriate for dynamic mesh.

poya0070 September 7, 2013 13:17

negative
 
Quote:

Originally Posted by abhiramBA (Post 443411)
Hello,
I am trying to simulate the oscillatory motion of an airfoil. I have successfully compiled my udf and the library is also loaded. I do not know what settings I should use in the dynamic mesh. Only the airfoil seems to oscillate and the grid stays as it is. :confused:
Also, when I solve, I get an error saying "Update-Dynamic-Mesh failed. Negative cell volume detected."
Kindly guide me through the dynamic meshing.




about this problem i study in fluent lecture that must be to have a skewness less than 0.7 or acceptable(less than 0.9-0.95, i dont know more).
but in my project(same ur project) resolve this notice and problem yet appear(Although in more time step) and in preview mesh motion the quality orthogonal after several time step is less than 0.05. and then error ......

what setting in remeshing and smothing is required to resolve this problem ?


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