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Micro nozzle-SLIP velocity UDF

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Old   January 15, 2010, 01:54
Default Micro nozzle-SLIP velocity UDF
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Hi There,
I am trying to simulate the supersonic flows through a rectangular C-D nozzle in the slip region with Kn number in the range of 0.01 to 0.1. The throat height is about 2micron. The inlet total pressure is kept at 100kPa and the outlet pressure at 30, 10kPa etc. I am using density based solver.
Now I am facing difficulties in incorporating the slip boundary condition at the wall. I am trying to use the well known Maxwell's first order slip boundary condition as us=lambda*du/dn. lambda is the mean free path.
As far I as realize, I have to input the slip velocity in terms of "specified shear" at the wall. Which macro I have to use in the udf (C_U_G(c,t) or C_U_RG(c,t))?
I think there are many experts in this forum who solved this type of problem. Could anyone help me by sending me the udf for slip bc?
Thanks in advance
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Old   July 1, 2010, 08:17
Post slip velocity
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did you get bc code?
i have collect some code ?
but little problem to compile it in fluent
let's to study it?
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