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-   -   Correct turbmodel for airflow with Re 55000 (http://www.cfd-online.com/Forums/openfoam-solving/60105-correct-turbmodel-airflow-re-55000-a.html)

newbee July 22, 2006 03:56

Hello! Im trying to model a
 
Hello!

Im trying to model a an airflow in a channel with Re = 55000. Im not sure which turbmodel to use for this but most of the models that i have tried have ended up with results looking too laminar compared with experimental values. I might be calculating the k and epsilon BC/IC values wrongly.

The way i try to calculate them is:
k = 0,002*Ub*pow(2)
ļ„epsilon = k*pow(3/2)/(0,3*Dh)

where Ub is bulkvelocity and Dh is the hydralic diameter.

So far i have treated the flow as higher turbulent and used wallFunctions with zeroGradient on k.

Does anyone have a suggestion for me what to do to make my flow look more turbulent?

This image illustates my flow profile. the upper patch is a wall and the three others are symmetryplanes. According to the experemental data the magnetude of U should not be higher then 25.2 m/s.

http://www.cfd-online.com/OpenFOAM_D...ges/1/2768.jpg

Thanks
/Erik

newbee July 22, 2006 04:30

I forgot to mention that I wan
 
I forgot to mention that I want a turbmodel for incompressible flow and the calculations are to be steady state.


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