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The nutUwallfunction in the LES

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Old   March 20, 2018, 21:24
Unhappy The nutUwallfunction in the LES
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Dear everyone.

It's my first time using nutUwallfunction . when I set the nutUwallfunction. I meet some problem.And I am not sure If I am correct.

I use Smagorinsky model and incompress model.and in the /0/nut file,I set

surface
{
type nutUWallfunction;
value uniform 0;
}

And in my 0/U file
I set
{
type fixedValue;
value uniform ( 0 0 0 );
}


1. So is it correct?
2. when I use nutUwallfunction ,what's meaning of the 'uniform 0' under the 'nutUwallfunction'?

I wish someone can help me.Now I am very worried.
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Old   March 21, 2018, 01:06
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Quote:
Originally Posted by TangYuanzhe View Post
what's meaning of the 'uniform 0' under the 'nutUwallfunction'?
This is the initial value. Don't mind for it. The real value will be calculated by the wall function und the course of calculated time.
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Old   March 21, 2018, 01:32
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Dear Uwe Pilz

So whether the 'U' and 'nut' setting is correct?
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Old   March 21, 2018, 03:52
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Whether ist is correct or not depends on what you wish to simulate (which properties you need at your walls / patches).
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Old   March 22, 2018, 02:25
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Quote:
Originally Posted by TangYuanzhe View Post
So whether the 'U' and 'nut' setting is correct?
If your surface is supposed to behave like a solid surface in a domain filled with a fluid and if you want 0 m/s flow velocity at your surface, than those settings are correct.
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