[derekm]

What buoyancy corrections are available in openfoam for the RANS turbulence models?
My interest is in thermal plumes inside cavities at rayleigh numbers around 10^9 to 10^10. The standard K-e turbulence model gives poor results compared to experiments.
Looking at the paper by Kumar & Dewan 2013, it looks that there are worthwhile improvements possible. Has anyone implemented these corrections or similar in OpenFoam?

[agustinvo]

AFAIK, there are no production terms that take into account the buoyancy effects.

// Turbulent kinetic energy equation
tmp<fvScalarMatrix> kEqn
(
fvm::ddt(k_)
+ fvm::div(phi_, k_)
- fvm::laplacian(DkEff(), k_)
==
G
- fvm::Sp(epsilon_/k_, k_)
);

// Dissipation equation
tmp<fvScalarMatrix> epsEqn
(
fvm::ddt(epsilon_)
+ fvm::div(phi_, epsilon_)
- fvm::laplacian(DepsilonEff(), epsilon_)
==
C1_*G*epsilon_/k_
- fvm::Sp(C2_*epsilon_/k_, epsilon_)
);

you should check the term you want to include, copy the model and rename it, and include those terms. Then compile you library by including this new directory.