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problems with calculating pressure coefficient

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Old   October 7, 2014, 02:33
Default problems with calculating pressure coefficient
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Elvira
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Hey
I'm simulating a flow around a NACA-profile. For this I want to calculate the pressure coefficient cp. I already added the following lines in my controldict:

pressureToolsl
{
type pressureTools ;
functionObjectLibs ("libutilityFunctionObjects.so");
calcTotal no;
calcCoeff yes;
}

Did I forget anything?

when I try to calculate this there are problems with the freestreampressure pinf.
My boundary say that I've got a velocity at the inlet and a pressure at the outlet given.
so how can I change my files to get the pressure coeffient?

hope you understand my question
thanks at all

regards Ernie10
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Old   October 7, 2014, 07:59
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James Rodgers
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Hi Ernie,

I'm by no means an expert but when through a similar exercise a week ago. I found that to calculate the coefficients both static and total you need to specify the reference static pressure and reference velocity within the pressureTools {}. OF didn't pick up the values from the boundary conditions. I think I ended up specifying also the reference density although this is superfluous for the incompressible simulation I was running.

Cheers,

James
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Old   October 7, 2014, 08:49
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Elvira
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ok that sounds plausible.
do you maybe know how I can tell OF to take the information about the pressure and velocity both at the inlet?

cheers
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boundary condition p, freestream pressure, pressure coefficient

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