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sasanghomi September 17, 2013 07:41

mut and alphat & compressible flow
Hi foamers ,

I have a question about setting mut and alphat file in the 0 directory .

I checked rhopimpleFoam tutorial . In this case all values of mut and alphat on the walls are 0 .

type mutwallFunction;
------> for mut
value uniform 0;

type alphatwallFunction;
------> for alphat
value uniform 0;

Also I checked kEpsilon.C in this source code I found a formula for calculating mut and alphat .

mut_ = Cmu_*rho_*sqr(k_)/epsilon_;
alphat_ = mut_/Prt_;

I want to create a case by coldEngineFoam . So I should set mut and alphat file and I am confusing about setting these files.
Please anybody guide me. I should set uniform 0 for them or I should calculate them by using their formula . Why in the tutorial the values have set uniform 0 ??

I appreciate any help from you.
Thanks and best regards,

nimasam September 17, 2013 12:54

as much as i know ;), when you are using wall function, the value is place holder! so that value is not important and the value of variable will be calculated based upon correlation

sasanghomi September 17, 2013 14:42

Thank you very much for your reply.

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