[gxy200992243]

Hi, everyone!

I am confused about the difference between the expressions of divdevreff in GenEddyVisc and GenSGSStress.

In GenEddyVisc,

tmp<fvVectorMatrix> GenEddyVisc::divDevReff(volVectorField& U) const
{
    return
    (
      - fvm::laplacian(nuEff(), U)
      - fvc::div(nuEff()*dev(T(fvc::grad(U))))
    );
}

In GenSGSStress,

tmp<fvVectorMatrix> GenSGSStress::divDevReff
(
    volVectorField& U
) const
{
    if (couplingFactor_.value() > 0.0)
    {
        return
        (
            fvc::div(B_ + couplingFactor_*nuSgs_*fvc::grad(U))
          + fvc::laplacian
            (
                (1.0 - couplingFactor_)*nuSgs_, U, "laplacian(nuEff,U)"
            )
          - fvm::laplacian(nuEff(), U)
        );
    }
    else
    {
        return
        (
            fvc::div(B_)
          + fvc::laplacian(nuSgs_, U, "laplacian(nuEff,U)")
          - fvm::laplacian(nuEff(), U)
        );
    }
}

I think B is neglected in the expression from GenEddyVisc. I find that almost all the eddy viscosity models include GenEddyVisc.H, but none of them includes GenSGSStress.H. Why is B neglected? Will this B make a big difference?

Billions of thanks!

[gxy200992243]

Just forget about this thread, I made a very terrible mistake.............

[syavash]

Originally Posted by gxy200992243

Just forget about this thread, I made a very terrible mistake.............

Hi,

I have a related question, I hope you can provide me some insight. Why nuSgs is included in GenSGSStress??! I look into the code and I see that nuSgs IO state is set to NO_READ, so how and why it is calculated?!

Thanks,
Syavash