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-   -   Specify Inlet Velocity Profile (http://www.cfd-online.com/Forums/ansys/73812-specify-inlet-velocity-profile.html)

JHardes March 17, 2010 15:10

Specify Inlet Velocity Profile
 
Hey folks,

I am working on an assignment for my CFD class. The goal is to simulate flow over a backward facing step in a 2-D duct, and use the results to evaluate the performance of different turbulence models. We have experimental data to compare with.

The inlet to the domain is 4 step-heights upstream of the step, so the inlet velocity profile must be specified. We are using a ln model for the profile, but both the top and bottom of the duct is "no-slip" so the same equation cannot be used from top to bottom.

I want to use something like this:

LIBRARY:
CEL:
EXPRESSIONS:
!IF y <= 0.0635
InletProfile = 0.6937*((4.461[m s^-1]*ln(121930*((y/0.0127[m])-1))) + 5[m s^-1])
!ELSE IF y > 0.0635
InletProfile = 0.6937*((4.461[m s^-1]*ln(121930*(((0.11431-y)/0.0127[m]))))+5[m s^-1])
END
END
END
END

Doesn't work (obviously?). I have been reading into it. Fortran?

Can someone point me in the right direction?

Thanks,

Jacob

JHardes March 17, 2010 15:59

Oops.
 
I am working in CFX.


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