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Floating point exception and increasing corruant numbers

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Old   September 5, 2022, 14:55
Question Floating point exception and increasing corruant numbers
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Eman Eal is on a distinguished road
I am attempting to set up my first real simulation after doing several tutorials.
Currently I have successfully created a mesh for my system. In the end I will need a fairly complicated system but currently I am just attempting to get the simulation to run and am planning to add in features one at a time.
Currently I am attempting to simulate incompressible flow in a region that is adjacent to a spinning shaft.
I can get the simulation to run successfully if I don't have the wall rotating but if I add any conditions that would cause motion in the region my corruant number quickly grows, and then after a point I get the following error.

Time = 0.005s

Courant Number mean: 0.0642621 max: 1.20394
#0 Foam::error:rintStack(Foam::Ostream&) at ??:?
#1 Foam::sigFpe::sigHandler(int) at ??:?
#2 ? in "/lib/x86_64-linux-gnu/libc.so.6"
#3 Foam::symGaussSeidelSmoother::smooth(Foam::word const&, Foam::Field<double>&, Foam::lduMatrix const&, Foam::Field<double> const&, Foam::FieldField<Foam::Field, double> const&, Foam::UPtrList<Foam::lduInterfaceField const> const&, unsigned char, int) at ??:?
#4 Foam::symGaussSeidelSmoother::smooth(Foam::Field<d ouble>&, Foam::Field<double> const&, unsigned char, int) const at ??:?
#5 Foam::smoothSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
#6 ? in "/opt/openfoam10/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#7 ? in "/opt/openfoam10/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#8 ? in "/opt/openfoam10/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#9 ? in "/opt/openfoam10/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#10 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#11 ? in "/opt/openfoam10/platforms/linux64GccDPInt32Opt/bin/icoFoam"
Floating point exception (core dumped)

I assume that my simulation is set up incorrectly. Does anyone have experience with similar errors?

This is my U file at 0:

/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 10
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class volVectorField;
object U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 1 -1 0 0 0 0];

internalField uniform (0 0 0);

boundaryField
{
symPlane
{
type symmetryPlane;
}

hotInlet
{
type zeroGradient;
}

coldInlet
{
type zeroGradient;
//value uniform (0 0 -.001);
}

circOutlet
{
type zeroGradient;
}

axialOutlet
{
type zeroGradient;
}

rotatingWall
{
// type noSlip;
type rotatingWallVelocity;
origin (0 0 -20);
axis (0 1 0);
omega 0.1;
}

staticWall
{
type noSlip;
}

defaultFaces
{
type empty;
}
}

my controlDict:
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 10
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class dictionary;
location "system";
object controlDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

application icoFoam;

startFrom startTime;

startTime 0;

stopAt endTime;

endTime 1;

deltaT .001;

writeControl runTime;

writeInterval 1;

purgeWrite 0;

writeFormat ascii;

writePrecision 6;

writeCompression off;

timeFormat general;

timePrecision 6;

runTimeModifiable true;

}
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 10
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class dictionary;
location "system";
object controlDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

application icoFoam;

startFrom startTime;

startTime 0;

stopAt endTime;

endTime 1;

deltaT .001;

writeControl runTime;

writeInterval 1;

purgeWrite 0;

writeFormat ascii;

writePrecision 6;

writeCompression off;

timeFormat general;

timePrecision 6;

runTimeModifiable true;

}


my fvSchemes:

/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 10
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class dictionary;
location "system";
object fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

ddtSchemes
{
default steadyState;
}

gradSchemes
{
default leastSquares;
}

divSchemes
{
default none;
div(phi,U) Gauss linearUpwind grad(U);
//div(div(phi,U)) Gauss linear;
}

laplacianSchemes
{
default Gauss linear corrected;
}

interpolationSchemes
{
default linear;
}

snGradSchemes
{
default corrected;
}


and my fvSolutions:

/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 10
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
format ascii;
class dictionary;
location "system";
object fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

solvers
{
p
{
solver PCG;
preconditioner DIC;
tolerance 1e-06;
relTol 0.05;
}

// pFinal
// {
// $p;
// relTol 0;
// }

U
{
solver smoothSolver;
smoother symGaussSeidel;
tolerance 1e-05;
relTol 0;
}
}

PISO
{
nCorrectors 2;
nNonOrthogonalCorrectors 0;
pRefCell 0;
pRefValue 0;
}

I have an image of the mesh but am having trouble uploading it to this post because it asks for a url, does anyone know a good way to do this?

I suspect that the issue is linked to the fact that the corruant number increases every time step until it becomes larger than 1.
I have also tried simply defining a slow flow from one of the inlets and that causes a similar error. I tried a few divergence schemes as well but that just changed when the error occurred. I am hoping that I have committed some common rookie mistake so I figured I would ask for help.
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