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-   -   laminar pipe flow with buoyantSimpleRadiationFoam and janafThermo crashes (http://www.cfd-online.com/Forums/openfoam/80519-laminar-pipe-flow-buoyantsimpleradiationfoam-janafthermo-crashes.html)

Fabian September 28, 2010 15:01

laminar pipe flow with buoyantSimpleRadiationFoam and janafThermo crashes
 
Hi all,

I try to simulate a laminar (Re~ 200) pipe flow with constant wall temperature. I planned to use buoyantSimpleRadiationFoam, since I want to activate later on a radiation model. So far my mesh is not axis symmetric yet; it is just a pretty fine 2D gambit mesh which I translated via fluentMeshToFoam. Later on I want to use makeAxialMesh to simulate axis symmetry. Anyhow, since I have high temperature gradients (1000K at the wall and inflow temperature of 300K), I want to use janafThermo to calculate cp as a function of T. My calculation fails with the message:

Foam Fatal Error: attempt to use janafThermo<equationOfState> out of temperature range 200->6000; T = 137.957

I also tried to set the wall temperature to 300K - same result. anybody have a clue, why this occurs? Maybe wrong Janaf parameter? I used a parameter set from an oxidizer with MW like air, which I found in one of the combustion tutorials. Also, my velocity field looks really weird for a laminar pipe flow.
The folder constant/ contains following files:
g:
dimensions [0 1 -2 0 0 0 0];
value (9.81 0 0 );

RASProperties:
RASModel laminar;
turbulence on;
printCoeffs on;

thermophysicalProperties:
thermoType hPsiThermo<pureMixture<sutherlandTransport<specieT hermo<janafThermo<perfectGas>>>>>;
mixture air 1 28.8504
200 6000 1000

pRef 101325;

radiationProperties:
standard file from corresponding tutorial case

The folder system/ contains following files:
controlDict:
application buoyantSimpleRadiationFoam;
startFrom latestTime;
startTime 0;
stopAt endTime;
endTime 1;
deltaT 1e-05;
writeControl timeStep;
writeInterval 50;
purgeWrite 0;
writeFormat ascii;
writePrecision 6;
writeCompression uncompressed;
timeFormat general;
timePrecision 6;
runTimeModifiable yes;

fvSchemes:
ddtSchemes
{
default steadyState;
}
gradSchemes
{
default Gauss linear;
}
divSchemes
{
default none;
div(phi,U) Gauss upwind;
div(phi,h) Gauss upwind;
div((muEff*dev2(grad(U).T()))) Gauss linear;
}
laplacianSchemes
{
default none;
laplacian(muEff,U) Gauss linear corrected;
laplacian((rho*(1|A(U))),p) Gauss linear corrected;
laplacian(alphaEff,h) Gauss linear corrected;
laplacian(gammaRad,G) Gauss linear corrected;
}
interpolationSchemes
{
default linear;
}
snGradSchemes
{
default corrected;
}
fluxRequired
{
default no;
p;
}


fvSolution:
solvers
{
p
{
solver PCG;
preconditioner DIC;
tolerance 1e-08;
relTol 0;
}
U
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-05;
relTol 0;
}
h
{
solver PBiCG;
preconditioner DILU;
tolerance 1e-05;
relTol 0;
}
rho
{
solver PCG;
preconditioner DIC;
tolerance 1e-08;
relTol 0;
}
G
{
solver PCG;
preconditioner DIC;
tolerance 1e-08;
relTol 0;
}
}
SIMPLE
{
nNonOrthogonalCorrectors 0;
pRefCell 0;
pRefValue 0;
}
relaxationFactors
{
rho 0.7;
p 0.2;
U 0.7;
h 0.5;
G 0.7;
}

Boundary Conditions:

Temperature:
dimensions [0 0 0 1 0 0 0];
internalField uniform 300;
boundaryField
{
wall
{
type fixedValue;
value uniform 1000.0;
}
axis
{
type symmetryPlane;
}
outlet
{
type zeroGradient;
}
inlet
{
type fixedValue;
value uniform 300.0;
}
frontAndBackPlanes
{
type empty;
}
}

alphat:
dimensions [1 -1 -1 0 0 0 0];
internalField uniform 2.8739e-05;
boundaryField
{
wall
{
type zeroGradient;
}
axis
{
type symmetryPlane;
}
outlet
{
type zeroGradient;
}
inlet
{
type fixedValue;
value uniform 2.8739e-05;
}
frontAndBackPlanes
{
type empty;
}
}

mut:
dimensions [1 -1 -1 0 0 0 0];
internalField uniform 1.983e-05;
boundaryField
{
wall
{
type zeroGradient;
}
axis
{
type symmetryPlane;
}
outlet
{
type zeroGradient;
}
inlet
{
type fixedValue;
value uniform 1.983e-05;
}
frontAndBackPlanes
{
type empty;
}
}

Velocity:
dimensions [0 1 -1 0 0 0 0];
internalField uniform (0.081 0 0);
boundaryField
{
wall
{
type fixedValue;
value uniform (0 0 0);
}
axis
{
type symmetryPlane;
}
outlet
{
type zeroGradient;
}
inlet
{
type fixedValue;
value uniform (0.081 0 0);
}
frontAndBackPlanes
{
type empty;
}
}

Pressure:
dimensions [1 -1 -2 0 0 0 0];
internalField uniform 0;
boundaryField
{
wall
{
type zeroGradient;
}
axis
{
type symmetryPlane;
}
outlet
{
type fixedGradient;
gradient uniform -1.2;
}
inlet
{
type fixedValue;
value uniform 101325;
}
frontAndBackPlanes
{
type empty;
}
}

Fabian September 29, 2010 11:38

Sorry, I forgot to mention that I am using OpenFOAM 1.6
best, Fabian


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