| Werne |
December 12, 2014 09:20 |
rhoSimpleFoam - strange behaviour of the residuals
1 Attachment(s)
Hey,
I'm getting some strange results for the residuals of my simulation. For the first 2000 iterations it looks ads if the simulation will converge. However, afterwards I'm getting strange "jumps" in the values of the residuals, as you can see in the attached plot.
I didn't change any files or values during the simulation.
Does anybody know what could be source of this behaviour?
I'm using rhoSimpleFoam with the following fvSchemes and fvSolution files:
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.2.2 |
| \\ / 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;
}
divSchemes
{
default bounded Gauss upwind;
div(phi,U) bounded Gauss upwind;
div((muEff*dev2(T(grad(U))))) Gauss linear;
div(phi,e) bounded Gauss upwind;
div(phi,omega) bounded Gauss upwind;
div(phi,k) bounded Gauss upwind;
div(phi,Ekp) bounded Gauss upwind;
}
laplacianSchemes
{
default Gauss linear corrected;
laplacian(muEff,U) Gauss linear corrected;
laplacian(alphaEff,e) Gauss linear corrected;
laplacian((rho*(1|A(U))),p) Gauss linear corrected;
laplacian(DomegaEff,omega) Gauss linear corrected;
laplacian(DkEff,k) Gauss linear corrected;
}
interpolationSchemes
{
default linear;
}
snGradSchemes
{
default corrected;
}
fluxRequired
{
default no;
p ;
}
// ************************************************************************* //
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.2.2 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
solvers
{
p
{
solver GAMG;
tolerance 1e-08;
relTol 0.05;
smoother GaussSeidel;
cacheAgglomeration off;
nCellsInCoarsestLevel 20;
agglomerator faceAreaPair;
mergeLevels 1;
}
U
{
solver smoothSolver;
smoother GaussSeidel;
nSweeps 2;
tolerance 1e-08;
relTol 0.1;
}
e
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-08;
relTol 0.1;
}
"(k|omega)"
{
$U;
tolerance 1e-09;
relTol 0.1;
}
}
SIMPLE
{
nNonOrthogonalCorrectors 2;
rhoMin rhoMin [ 1 -3 0 0 0 ] 0.5;
rhoMax rhoMax [ 1 -3 0 0 0 ] 10;
residualControl
{
p 1e-8;
U 1e-8;
e 1e-8;
// possibly check turbulence fields
"(k|epsilon|omega)" 1e-8;
}
}
relaxationFactors
{
fields
{
p 0.1; //0.1
rho 0.05; //0.05
}
equations
{
U 0.7; //0.7
k 0.7; //0.7
omega 0.7; //0.7
e 0.7; //0.7
}
}
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