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Correct turbmodel for airflow with Re 55000

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Old   July 22, 2006, 03:56
Default Hello! Im trying to model a
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newbee
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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.



Thanks
/Erik
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Old   July 22, 2006, 04:30
Default I forgot to mention that I wan
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newbee
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I forgot to mention that I want a turbmodel for incompressible flow and the calculations are to be steady state.
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