- **OpenFOAM Running, Solving & CFD**
(*http://www.cfd-online.com/Forums/openfoam-solving/*)

- - **Compressible Reynolds Stress Models**
(*http://www.cfd-online.com/Forums/openfoam-solving/59482-compressible-reynolds-stress-models.html*)

Hi all,
I'm working on a LowRHi all,
I'm working on a LowReynoldsNumber ReynoldsStressModel based on Wilcox's. I just have a couple of questions regarding existing compressible RSMs. 1) I guess that laminar behavior and modeling is not affected by turbulence models selections. I mean that a non-turbulent case could always be modeled as turbulent with mut=0. And results should not be influenced by the choice of turbulent model. So why divRhoR for RSM is returning: fvc::div( rho_ * R_,"divRhoR") - fvm::laplacian(muEff(), U) + fvc::laplacian(mut_, U) resulting for a laminar case in - fvm::laplacian(mu(), U) that is not consistent with the other two equation models: - fvm::laplacian(mu(), U) - fvc::div(mu()*dev2(fvc::grad(U)().T())) ? Might it be a bug? Possible fix: fvc::div( rho_ * R_,"divRhoR") - fvm::laplacian(muEff(), U) + fvc::laplacian(mut_, U) - fvc::div(mu()*dev2(fvc::grad(U)().T())) 2) Are there any specific solvers for RSM? 3) How do you manage (I'm still working with OF-1.3 and I saw inthe new version this problem is oslved) the possibility for R to result non-symmetric? 4) How do you model turbulent heat flux? divRhoUh does not seem to be implemented in neither Launder&Gibson nor LRR, so they still model isotropic turbulent heat flux. I would like to use Generalized Gradient Diffusion Hypothesis. So my divRhoUh results to be: - fvc::div(mut_* 3.3 *(R_ & tgradh())/k_,"divRhoUh") + fvc::laplacian(mut_* alphah, h) - fvm::laplacian(alphaEff(), h) I found constant 3.3 to be valid for flat plates (Ameri 2002). Is there anyone who have already done it and could suggest me other expressions? Thanks a lot for your time, Cosimo |

All times are GMT -4. The time now is 19:05. |