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-   -   Smagorinsky model (http://www.cfd-online.com/Forums/openfoam-solving/60150-smagorinsky-model.html)

sylvain91 June 22, 2006 06:29

I ran a LES calculation using
 
I ran a LES calculation using the Smagorinsky model and I was suprised to see that no post data files existed for k. I had a look at the code and apparently in this turbulent model the subgrid scale turbulent energy is of course calculated and normally returned. I know some data can be added using PostProcessing from FoamUtilities but I could not figure out where k was. If someone knows how to get it?

Moreover from the code I doubt about the function which returns k in Smagorinsky.H: the square of delta and deviatoric component of D.

Description
<pre>
The Isochoric Smagorinsky Model
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Algebraic eddy viscosity SGS model founded on the assumption that
local equilibrium prevails, hence

B = 2/3*k*I - 2*nuEff*dev(D)

where

D = symm(grad(U));
k = (2*ck/ce)*delta^2*||D||^2
nuSgs = ck*sqrt(k)*delta
nuEff = nuSgs + nu
</pre>

SourceFiles
Smagorinsky.C


Farther in Smagorinsky.H:

//- Return SGS kinetic energy
// calculated from the given velocity gradient
tmp<volscalarfield> k(const tmp<voltensorfield>& gradU) const
{
return (2.0*ck_/ce_)*sqr(delta())*magSqr(dev(symm(gradU)));
}


If someone could help me telling me what he thinks about it? Perhaps I did not analyse the code correctly? Thanks


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