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Brayton November 29, 2000 00:51

Reason of divergence ?
 
Hi,

I am writing a finite volume code. But I met a problem. When using finer grids, the computation becomes divergent! What is the reason ?

Thank in advance.


Mukhopadhyay November 29, 2000 02:05

Re: Reason of divergence ?
 
Please refer to the thread 'convergence problem' in this forum posted by 19/20 Nov. Also look for the archive. If there is any specific topic please leave message for discussion.

frederic felten November 29, 2000 14:34

Re: Reason of divergence ?
 
hi there,

What kind of grid arrangement are you using? Staggered or Collocated? If you are using a collocated arrangement, well be sure that you're treating correctly the pressure-velocity coupling.You also need to pay special attention to the velocity correction. Check the following article: Morinishi, Lund, Vasilyev and Moin. "Fully Conservative Higher Order Finite Difference Schemes for Incompressible Flow". J. Comp. Phys 143, 90-124, 1998. Can be downloaded at: http://mae.uta.edu/~lund/ Finally be sure that your time step does verify the CFL condition.

I hope this helps,

Sincerely,

Frederic Felten CFD Laboratory, UT Arlington. http://utacfdb.uta.edu/

Brayton December 2, 2000 23:34

Re: Reason of divergence ?
 
Thank you all!


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