omegaWallFunction implementation
Hello,
I'm studying the implementation of the incompressible omegaWallFunction. http://foam.sourceforge.net/docs/cpp/a09165_source.html Code:
00207 scalar omegaVis = 6.0*nuw[faceI]/(beta1_*sqr(y[faceI])); This clearly becomes oo when y approaches 0. Does this account for the turbulence damping near the wall? Next question: What is G? Code:
00173 volScalarField& G = Code:
00213 G[faceCellI] = I'm especially clueless that the last part with the G is about? Thanks! Florian 
Hi Florian,
For the second question, the followings will be of help:
Hope this helps, Fumiya 
Hello all,
I noticed that the logarithmic component of omega1 in the code is not representative of the Menter 2001 paper. The code is: Code:
scalar omegaLog = sqrt(k[faceCellI])/(Cmu25*kappa_*y[faceI]); Menter 2001 gives: Where C_mu = 0.09. Why the difference? A message above makes reference to the following website: http://www.cfdonline.com/Wiki/Two_e...bulence_models The last term of the last equation in the "Standard Wall Functions" section at that link matches the code, but it is still not clear why the code chose the equation that was selected (Wilcox 1994 eq 6.84) and not that which was defined in Menter 2001. Does anyone know why the code is what it is, and not in line with Menter 2001? Thanks, Daniel 
Implementation of SST Wall Function (Menter)
Hi,
I am also wondering why is there difference between Menter Wall function definition and OF wall function definition. do you have an answer now ?? 

Menter 2001 Paper
Hello Andrea,
Unfortunately I also dont hv Menter 2001 Paper. Nevertheless, I have requested someone on CFD online. He hopefully will share it with me. If I receive it, will surely share it with you :) 

Hello,
The COBEM paper is available in the public domain here: http://www.abcm.org.br/anais/cobem/2001/home.htm > just go to Lectures link It was posted by someone else in this thread, #43: http://www.cfdonline.com/Forums/ope...tpaper3.html It looks like you are correct, there must have been an error in my post above because sqrt(Cmu = 0.09) = 0.3 and then everything matches up (if it is Cmu^1/2 instead of ^1/4). Apologies for the confusion caused by this error. Dan 
Menter 2001 Paper
Hello Andrea,
Daniel "Dancfd" have sent me the Esh & Menter Paper. If you wish I can forward it to you or you can request Daniel for it :) 
Thanks a lot Daniel and Ali,
so everything is ok now, we can say OF is correct! ;) Best regards, Andrea 
Smoothing Function for Friction Velocity
Hi Adrea/Daniel,
I was wondering the Omega_Log term is defined by Menter as Omega_Log = U_tau/(0.3*kappa*y) where U_tau is calculated from U_Vis = U1/y & U_Log = U1/((ln(y)/k)+c) U_Tau = ( (u_Vis)^4 + (U_Log)^4)^(1/4) But in OF omega_Log is approximated by I think Spalding assumption i.e. U_Tau = cmu^(1/4)*sqrt(k) So, what if Menter U_Tau is used in omegaWallFunction .. will that improve the results i.e. mesh independence 
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