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Normal to boundary velocity

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Old   January 21, 2006, 20:39
Default I have to model a pipe with a
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Alberto Passalacqua
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I have to model a pipe with a circular corona inlet all around the pipe circumference.

I have to specify a velocity normal to this boundary. How can I do it in OpenFOAM?

Thanks in advance
Alberto
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Old   January 23, 2006, 05:30
Default surfaceNormalFixedValue (in Op
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Mattijs Janssens
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surfaceNormalFixedValue (in OpenFOAM/lnInclude/surfaceNormalFixedValueFvPatchField.H)

needs a 'refValue' entry which is the outwards pointing velocity (so negative for inflow)
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Old   January 23, 2006, 18:30
Default Thanks!
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Alberto Passalacqua
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Thanks!
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Old   June 21, 2007, 10:12
Default Hi, it seems that I have a
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Fabian Braennstroem
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Hi,

it seems that I have a similar problem... I would like to calculate a hvac duct and have to set the inlet velocity normal to the boundary. Unfortunately, I do not understand, what Mattijs wrote as a hint!?

Regards!
Fabian
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Old   June 21, 2007, 14:11
Default If the boundary is flat, use f
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Alberto Passalacqua
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If the boundary is flat, use fixedValue and specify the appropriate components of the velocity.

If it's not flat You can use:

type surfaceNormalFixedValue;
refValue uniform Umag;

As Mattijs said, if you want your flow to enter your domain, Umag has to be negative.

Regards,
Alberto
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Old   June 22, 2007, 02:39
Default Hi, On a similar note, if I
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Hi,

On a similar note, if I were to simulate boundary layer suction or blowing, would it be valid to use an ordinary wall boundary condition with a (strictly) normal velocity specified (either by using fixedValue or surfaceNormalFixedValue), or would a specialized boundary condition need to be build?

Also, could, for moderate normal velocities, a wall function still be used? Or will a low-Re turbulence model be required?

best regards,
Roland
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Old   July 3, 2007, 08:16
Default Hi Alberto, thanks for the
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Fabian Braennstroem
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Hi Alberto,

thanks for the help!

Regards!
Fabian
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