CFD Online Discussion Forums

Dear FOAMers,

I hope someone can help me:

As I read in the source code of the SSG turbulence model, the diffusion coefficients of $\epsilon$ and $\bf{R}$ are constructed as symmetrical tensors:

Code:

template<class BasicTurbulenceModel>

tmp<volSymmTensorField> SSG<BasicTurbulenceModel>::DREff() const

{

     return tmp<volSymmTensorField>

     (

         new volSymmTensorField

         (

             "DREff",

             (Cs_*(this->k_/this->epsilon_))*this->R_ + I*this->nu()

         )

     );

}

Now I'm wondering, how can the laplacian

Code:

fvm::laplacian(alpha*rho*DREff(), R)

be denoted in mathematical form. I had a look at the code but did not find a clear answer of how OpenFOAM produces it. In specific, I am trying to find out, in what kind of product the 2x2 diffusion matrix $\bf{\Gamma}$ $=\Gamma_{ij}$ and the 3x3 'Reynolds stress gradient' $\nabla \bf{R}$ $=r_{ijk}$ are coupled.

Regards