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problem stabilizing kw-sst..

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Old   August 8, 2016, 05:45
Default problem stabilizing kw-sst..
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Spockner
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Hi everyone,
I am encountering a strange problem while using kw-sst turbulence model in case of a 3d airfoil. In a very few steps omega and k both stop iterating (No of iterations = 0) and they seem to be converged, residuals being as low as 10^-15... I am using 10^-08 tolerance in the solver and 10^-04 as relTol... What could be the reason behind this behaviour?
Any help is appreciated..
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Old   August 8, 2016, 06:30
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Hyoung Min Suh
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What is the y+ value?
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Old   August 8, 2016, 07:05
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Yplus is 300
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Old   August 8, 2016, 14:45
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Mahdi Hosseinali
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I think your yplus is out of the log layer. What is your boundary conditions for the airfoil?
Also you gotta check which variable goes unstable first? Other than that, you can try outputting your results more frequent and visually check what is going wrong? works more than you think.
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Old   August 8, 2016, 15:25
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Shujaut H. Bader
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thanks, i will try doing these first to see if i get it working...
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