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Strange non converging beharvior

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Old   August 18, 2014, 19:51
Default Strange non converging beharvior
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Gregoire Junqua
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Hi all, I am using a k-omega SST with simpleFoam over a flat boundary.
I testing different inlet condition. For my first test I just use a log law.
But i am facing a non convergence of my simulation with Uy (vertical wind speed) residual after a nice decrease it increase to around 0.001.

I saw some topic speaking about it but they didn't gave the solution of this problem.

if you got any idea that i could try it would be helpful
Thanks
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Old   August 19, 2014, 09:54
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What boundary conditions do you have at the wall?
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Old   August 19, 2014, 10:30
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Quote:
Originally Posted by RodriguezFatz View Post
What boundary conditions do you have at the wall?
for k i got the standard one how
for omega it is omegaWallFunction
for nut nutKAtmRoughWallFunction
U it is fixed to 0

do you think it come from there?

I fixed it by using a simple grading in blockMeshDict. But if somebody could explain why.
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Old   August 19, 2014, 10:34
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Quote:
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for k i got the standard one how
What does that mean?

What y+ do you have?
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Old   August 19, 2014, 21:03
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What does that mean?
the zeroGradient one
for y+ I will have look later i am not in my work office
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