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Accessing C_mu within UDF

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Old   July 3, 2014, 04:26
Question Accessing C_mu within UDF
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Jack Chilvers
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Dear All,

I would like to access the parameter C_{\mu} for use within a Fluent UDF. To this end, could somebody please tell me the variable name such that:

cmu = <???>(cell_index, cell_thread);


Many thanks,
Jack
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Old   July 3, 2014, 06:48
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Manuel
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Well, maybe you can compute from its definition. But I don't know if you can access the viscous turbulence if you're not using Spalart-Allmaras. Maybe this works: (Cmu=turb.visc / density / K^2 * epsilon )

Code:
cmu=C_NUT(c,t)/C_R(c,t)/C_K(c,t)/C_K(c,t)*C_D(c,t);
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Old   July 3, 2014, 10:14
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Don't you mean C_MU_L(c,t)?
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Old   July 3, 2014, 11:31
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Manuel
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I have had a better look to the manual and saw that the turbulence eddy viscosity is given by C_MU_T(c,t).

So I correct what I said in previous post, you may compute c_mu as:

cmu=C_MU_T(c,t)/C_R(c,t)/C_K(c,t)/C_K(c,t)*C_D(c,t);

But I wonder... don't you set this parameter as a constant in the turbulence model panel? Why do you need to find it for a specific cell?
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