| pascool |
October 25, 2012 14:09 |
Problems solving T Equation in separated flow using a second Order Closure Model
Hi everybody,
I am trying to simulate the flow over a heated backward facing step by means of a modified simpleFoam solver which uses a second order Closure Model for the turbulent heat fluxes. The model worked pretty well in the heated turbulent channel. But it doesn't work for the Backward facing step in combination with a RSM turbulence model such as the LaunderGibson. I did a pre-calculation based on the RSM model and Fouriers Law for the scalar fluxes.
I already tried different solver settings and schemes in the fvSolvers and fvSolutions file.
Currently the files look as follows:
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
solvers
{
p
{
solver PCG;
preconditioner DIC;
tolerance 1e-08;
relTol 0.01;
}
U
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-08;
relTol 0.1;
}
k
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-08;
relTol 0.1;
}
epsilon
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-08;
relTol 0.1;
}
R
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-08;
relTol 0.1;
}
nuTilda
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-08;
relTol 0.1;
}
T BICCG 1e-08 0.01;
}
SIMPLE
{
nNonOrthogonalCorrectors 0;
}
relaxationFactors
{
p 0.3;
U 0.5;
k 0.5;
epsilon 0.5;
R 0.5;
nuTilda 0.5;
T 0.3;
}
// ************************************************************************* //
fvSchemes:
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
ddtSchemes
{
default steadyState;
}
gradSchemes
{
default Gauss linear;
grad(p) Gauss linear;
grad(U) Gauss linear;
}
divSchemes
{
default none;
div(phi,U) Gauss upwind;
div(phi,k) Gauss upwind;
div(phi,epsilon) Gauss upwind;
div(phi,R) Gauss upwind;
div(R) Gauss linear;
div(phi,nuTilda) Gauss upwind;
div((nuEff*dev(T(grad(U))))) Gauss linear;
div(phi,T) Gauss upwind;
div((Dp&grad(p))) Gauss linear;
div((S&grad(p))) Gauss linear;
}
laplacianSchemes
{
default none;
laplacian(nuEff,U) Gauss linear corrected;
laplacian((1|A(U)),p) Gauss linear corrected;
laplacian(DkEff,k) Gauss linear corrected;
laplacian(DepsilonEff,epsilon) Gauss linear corrected;
laplacian(DREff,R) Gauss linear corrected;
laplacian(DnuTildaEff,nuTilda) Gauss linear corrected;
laplacian(((nu|0.7123)+(nut|0.86)),T) Gauss linear corrected;
laplacian(kappaEff,T) Gauss linear corrected;
}
interpolationSchemes
{
default linear;
interpolate(U) linear;
}
snGradSchemes
{
default corrected;
}
fluxRequired
{
default no;
p ;
}
// ************************************************************************* //
The error message is as follows:
Code:
#0 Foam::error::printStack(Foam::Ostream&) in "/home/pascal/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#1 Foam::sigFpe::sigHandler(int) in "/home/pascal/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#2 in "/lib/x86_64-linux-gnu/libc.so.6"
#3 Foam::PBiCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/home/pascal/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#4 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/home/pascal/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libfiniteVolume.so"
#5
at simpleFoam_YSC_q.C:0
#6
in "/home/pascal/OpenFOAM/pascal-2.1.1/platforms/linux64GccDPOpt/bin/simpleFoam_YSC_q"
#7 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#8
in "/home/pascal/OpenFOAM/pascal-2.1.1/platforms/linux64GccDPOpt/bin/simpleFoam_YSC_q"
Floating point exception (core dumped)
Any help appreciated!
Regards,
Pascal |
