| McCharles |
June 9, 2016 07:52 |
Velocity Oscillation with rhoPimpleFoam
Hello Foamers,
i am currently trying to simulate a case with rhoPimpleFoam. While all the variables seemed to have converged, the velocity began to oscillate. I decreased the rexalation factor for U but that only damped the oscillation. For relaxation Factors smaller than 0.3, the Simulation will blow up. I .don't believe that there is something wrong with my BC, they worked for the majority of my simulations.
Please take a look at my residual plot, fvSchemes and fvSolution settings.
Plot:
https://www.dropbox.com/s/fsftmv6kvg...C2%AB.png?dl=0
Does anyone have a clue?
Thanks and Cheers!
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.3.1 |
| \\ / 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-06;
relTol 0.01;
}
pFinal
{
$p;
tolerance 1e-06;
relTol 0;
}
"(rho|U|h|e|k|epsilon|omega)"
{
solver smoothSolver;
smoother symGaussSeidel;
tolerance 1e-06;
relTol 0;
}
"(rho|U|e|h|k|epsilon|omega)Final"
{
$U;
tolerance 1e-06;
relTol 0;
}
}
PIMPLE
{
momentumPredictor yes;
transonic no;
nOuterCorrectors 60;
nCorrectors 2;
nNonOrthogonalCorrectors 1;
rhoMin rhoMin [ 1 -3 0 0 0 ] 0.5;
rhoMax rhoMax [ 1 -3 0 0 0 ] 20;
residualControl
{
"(U|k|epsilon)"
{
relTol 0;
tolerance 0.0001;
}
}
turbOnFinalIterOnly off;
}
relaxationFactors
{
fields
{
"p.*" 0.6;
"rho.*" 0.01;
}
equations
{
"(h|e|k|epsilon|omega).*" 0.7;
"U.*" 0.4;
}
//**************************************************************************************
Code:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.3.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
ddtSchemes
{
default Euler;
}
gradSchemes
{
default Gauss linear;
}
divSchemes
{
default bounded Gauss upwind;;
/*div(phi,U) bounded Gauss upwind;
div(phid,p) bounded Gauss upwind;
div(phiv,p) bounded Gauss upwind;
div(phi,K) bounded Gauss upwind;
div(phi,h) bounded Gauss upwind;
div(phi,k) bounded Gauss upwind;
div(phi,e) bounded Gauss upwind;
div(phi,epsilon) bounded Gauss upwind;
div(phi,R) bounded Gauss upwind;
div(phi,omega) bounded Gauss upwind;
div((rho*R)) bounded Gauss upwind;
div(R) bounded Gauss upwind;
div(U) bounded Gauss upwind;*/
div((muEff*dev2(T(grad(U))))) Gauss linear;
}
laplacianSchemes
{
default Gauss linear corrected;
}
interpolationSchemes
{
default linear;
}
snGradSchemes
{
default corrected;
}
fluxRequired
{
default no;
p ;
}
// ************************************************************************* //
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