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Rough baundary in atmospheric wind

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Old   August 18, 2008, 10:51
Default Hi! I am modeling the wind
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Majid Hojjat
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Hi!

I am modeling the wind effect on a cubic building. and first, to get the proper approaching flow (similar to experimental data) I am modeling an empty wind channel.
prescribing the inlet velocity, I produce the Ux profile. but for turbulence intensity (or k) using the inlet is not hopeful and I guess I should use a rough wall function to get the desired profile.

I tried using nutStandardRoughWallFunction but it was not really effective. even changing value of roughness length or... did not change anything.
To have a rough wall, is it enough just to add nutStandardRoughWallFunction as the physical type in boundary file and to specify roughness length and other parameters in /0/k ?

I am using OF 1.4.1 and I tried the mentioned problem in kEpsilon and kOmegaSSt as well as LES models.

Thanks!
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Old   August 18, 2008, 11:11
Default nut boundary conditions are on
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Eugene de Villiers
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nut boundary conditions are only effective in conjunction with the SpalartAllmaras model.
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Old   August 18, 2008, 11:30
Default thank you for your answer, so
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Majid Hojjat
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thank you for your answer,
so, there is no ready rough wall function to be used in other models?
and to maintain turbulence intensity profile I just have the choice of modifying the inlet values?
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Old   August 18, 2008, 12:15
Default For the other models the wall
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For the other models the wall functions are hard-coded.

Not sure about the turbulence intensity profile.
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