deathstar |
February 1, 2024 13:09 |
buoyantPimpleFoam diverges with the negative temperature
4 Attachment(s)
Hi,
I want to simulate a 3-D transient of external wind around buildings. The turbulent model was set K-epsilon. I tried to use the buoyantPimpleFoam solver in OpenFOAM 8, and after a few time steps, the solution diverges with the negative temperature error. I want to use buoyantPimpleFoam because I need to apply the Boussinesq approximation. The grid of the computational domain is shown in Figure. The output from checkMesh was OK. I think there is something wrong with pressure; I am not sure! I am new to OpenFoam, and any help would be highly appreciated.
The BCs are attached in the 0 folder, and the other case setups are presented below:
** thermophysical properties:
PHP Code:
thermoType { type heRhoThermo; mixture pureMixture; transport const; thermo eConst; equationOfState Boussinesq; specie specie; energy sensibleInternalEnergy; }
mixture { specie { molWeight 28.9; } equationOfState { rho0 1; T0 290; beta 3e-03; } thermodynamics { Cv 712; Hf 0; } transport { mu 1.8e-05; Pr 0.7; } }
fvSchemes:
PHP Code:
ddtSchemes { default Euler; }
gradSchemes { default leastSquares; }
divSchemes { default none;
div(phi,U) Gauss linearUpwind grad(U); div(phi,e) Gauss upwind;
div(phi,k) Gauss upwind; div(phi,epsilon) Gauss upwind;
div(phiv,p) Gauss linear; div(phi,K) Gauss linear;
div(phi,R) Gauss upwind; div(R) Gauss linear; div(phi,nuTilda) Gauss upwind;
div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear; }
laplacianSchemes { default Gauss linear corrected; }
interpolationSchemes { default linear; }
snGradSchemes { default corrected; }
fvSolution:
PHP Code:
solvers { "rho.*" { solver diagonal; }
p_rgh { solver GAMG; tolerance 1e-7; relTol 0.01;
smoother DICGaussSeidel; }
p_rghFinal { $p_rgh; relTol 0; }
"(U|e|k|epsilon)" { solver smoothSolver; smoother symGaussSeidel; tolerance 1e-05; relTol 0.1; }
"(U|e|k|epsilon)Final" { $U; relTol 0; } }
PIMPLE { momentumPredictor no; nOuterCorrectors 1; nCorrectors 2; nNonOrthogonalCorrectors 2;
pRefCell 0; pRefValue 0; }
Thank you! Attachment 98393
Attachment 98394
Attachment 98395
Attachment 98396
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