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-   -   Near wall treatment for k-e model (http://www.cfd-online.com/Forums/main/13423-near-wall-treatment-k-e-model.html)

raik May 5, 2007 08:30

Near wall treatment for k-e model
 
Hi, I have question abt k-e model with near wall treatment. Is this possible? and if yes then in which circumstances? I know that fluent have already this type, but why I am wondering is that k-e model starts from log layer (I have also doubt abt that) then why k-e model should have near wall treament option? bcoz k-e model is one type of turbulent core model? thanks


Phil May 5, 2007 12:22

Re: Near wall treatment for k-e model
 
isn't near wall treatment just enhanced heat transfer calculations?

Bignose May 6, 2007 02:42

Re: Near wall treatment for k-e model
 
The key phrase you are looking for here is "low Reynolds number" or "low-Re" turbulent models. They modify the terms in the k-epison model equations so that you can use the equations all the way up to the wall. Empircal dampening functions are added or modify the equations (mostly the epsion eqn) so that the equations are asymptotically consistent with the near-wall behavior. Wilcox's book Turbulence Modeling for CFD has a good introduction to some of the first generation low Re models. They have improved since that first generation, but they have also become much more complex.

Phil May 6, 2007 07:51

Re: Near wall treatment for k-e model
 
I thought the best low Re k-epsilon model was the RNG version.


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