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How can check the eddy viscosity at the wall with LES

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Old   August 14, 2015, 02:21
Default How can check the eddy viscosity at the wall with LES
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Sungjin Won
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Hi, I checked my code based on 3D turbulent channel flow model (Re_tau=180).

Staggered grid which contains eddy viscosity at the center of grid is used.

Due to the properties are placed on the grid center, I confused about checking the properties of eddy viscosity at the wall. When I plot the time averaged eddy viscosity data, the tendency doesn't look like going to zero.

The data starts from y+ = 0.583690705381331.

Thanks in advance.
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Old   August 14, 2015, 07:57
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Filippo Maria Denaro
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The static Smagorinsky eddy viscosity model cannot give zero at wall...
Usually, a dumping function is supplied
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Old   August 16, 2015, 04:38
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Quote:
Originally Posted by FMDenaro View Post
The static Smagorinsky eddy viscosity model cannot give zero at wall...
Usually, a dumping function is supplied
Thank you for replying!

As you said, static Smagorinsky eddy viscosity cannot give zero at wall.

But when if I wanna check the dynamic eddy viscosity, is there a way to check it?
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Old   August 16, 2015, 04:47
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Quote:
Originally Posted by sjwon1991 View Post
Thank you for replying!

As you said, static Smagorinsky eddy viscosity cannot give zero at wall.

But when if I wanna check the dynamic eddy viscosity, is there a way to check it?
in the dynamic procedure, the eddy viscosity function must go to zero at a wall, you can check by looking to the vertical profiles as you did in the previous figure
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