realizableKE hanging and then exploding
Hi foamers,
I have some problems with the k-epsilon realizable turbulent model. I already used it for other cases without troubles, so I'm not able to understand what's wrong or what I can improve. The simulation starts bad, hanging for several minutes, but then it seems to run: Code:
Time = 1 Code:
Time = 398 fvSolution Code:
solvers Code:
ddtSchemes |
Hi,
I have used realizableKE turbulence model for external aerodynamics with the following settings. fvSchemes: ddtSchemes { default steadyState; } gradSchemes { default Gauss linear; grad(p) Gauss linear; grad(U) Gauss linear; } divSchemes { default none; div(phi,U) Gauss SFCD; div(phi,k) Gauss SFCD; div(phi,epsilon) Gauss SFCD; div((nuEff*dev(grad(U).T()))) Gauss linear; } laplacianSchemes { default Gauss linear corrected; } interpolationSchemes { default linear; interpolate(U) linear; } snGradSchemes { default corrected; } fluxRequired { default no; p; } fvSolution: solvers { p { solver GAMG; tolerance 1e-7; relTol 0.1; smoother GaussSeidel; nPreSweeps 0; nPostSweeps 2; cacheAgglomeration on; agglomerator faceAreaPair; nCellsInCoarsestLevel 10; mergeLevels 1; }; U { solver PBiCG; preconditioner DILU; tolerance 1e-5; relTol 0.1; }; k { solver PBiCG; preconditioner DILU; tolerance 1e-5; relTol 0.1; }; epsilon { solver PBiCG; preconditioner DILU; tolerance 1e-5; relTol 0.1; }; } SIMPLE { nNonOrthogonalCorrectors 0; } relaxationFactors { p 0.3; U 0.7; k 0.7; epsilon 0.7; } Best regards, Stephane. |
Thank you very much for your help, I'll try to test your fvSolution file.
|
I also tried the fvSchemes and fvSolution settings suggested by Stephane, but I still have bounding epsilon problems - I can see epsilon and evaluated forces getting higher and higher.
Can you explain that? I already used k-epsilon realizable turbulent model without such problems, does it depend on the geometry? I tried to change relaxion factors till 0.2 without success (values get a little lower but always too big). What could I improve in my fvSolution and fvSchemes files? Thanks for your help, regards. |
realizableKE problem with OF1.71
Hi
I am trying to use Rke turbulence model in a case which runs OK using standard ke. Am I missing something when using Rke ? Has anybody has an example of what needs to be initialise when using Rke please ? When using ke I initialise k,e,R using standard tools as explained ijn OF user guide etc ? Do I need to add something elsewhen using Rke please ? Thanks for your help Regards Z. |
All times are GMT -4. The time now is 02:04. |