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k.vimalakanthan April 21, 2011 11:16

Issue with transition models
 
5 Attachment(s)
Hi guys,

Im trying to simulate a 2D flow around the S809 airfoil (see attached picture). Flow reynolds number is 2 million (2D grid with unity depth). Im using the SST gama theta transition model for my simulation, currently I have been faced with an unknown problem. A grid consisting of 1 million elements was used. The simulation was run for 5000 iterations (convergence history is attached). The turbulence intensity of 0.03% was used. Unusually the wall shear stress distribution (see attached picture) suggests a cross flow between the two ends of the wing (symmetry conditions). Because of this two different distribution of shear stress is obtained at the suction(top) surface. I was wondering if anyone else faced the same issue with the gama theta SST model. If so could you please tell me where I'm going wrong and please suggests a way to solve this problem.

Any help on this matter is greatly appreciated.

Thanks in advance :)

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ghorrocks April 26, 2011 22:15

Looks like you problem is more to do with this FAQ:

http://www.cfd-online.com/Wiki/Ansys...gence_criteria


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