CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   OpenFOAM Post-Processing (https://www.cfd-online.com/Forums/openfoam-post-processing/)
-   -   problems with calculating pressure coefficient (https://www.cfd-online.com/Forums/openfoam-post-processing/142675-problems-calculating-pressure-coefficient.html)

Ernie10 October 7, 2014 02:33

problems with calculating pressure coefficient
 
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

jrwrodgers October 7, 2014 07:59

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

Ernie10 October 7, 2014 08:49

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


All times are GMT -4. The time now is 07:31.