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error in openfoam

Hi

I was trying to simualte this case in openfoam using icoFoam, whose BCs are these.

and I'm getting this error

Courant Number mean: 53.8675 max: 11997.2
#0 Foam::error::printStack(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<double>&, 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/openfoam8/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#7 ? in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#8 ? in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#9 ? in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/icoFoam"
#10 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#11 ? in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/icoFoam"
Floating point exception (core dumped)

Please Help

these are my case files


OpenFOAM 23-07-21, 9:04 a.m. prth_bndl
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Hi,
The solver (icoFoam) you are using is transient. So it is necessary to evaluate CFL no and deltaT. If your mesh is unstructured and difficult to calculate CFL no manually, you can set deltaT as adjustable and specify maximum CFL no. It will calculate deltaT at every iteration for max CFL no you are specifying. Have a look at these two lines and modify/edit in your controlDict file:

writeControl adjustableRunTime;
maxCo 1.0;

Regards,
Divyesh Variya
23-07-21, 10:53 a.m. divyesh


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Hi I just want to know that how did you figured out the problem from these ten line error, I often get this ten line error many times some times it is related to wrong boundary types and boundary conditions and this time it was CFL no. Is there a documentaion of somekind which help in figuring out the problem, because floating point exception is always common among them.
23-07-21, 7:08 p.m. prth_bndl


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You can crack that from the error message itself. For example, in this case, first line says Courant no is 11997... Theoretically, it should be less than 1. So from your courant no formula, you can either fix deltaT or maxCo no or Velocity. Since your velocity is fixed and delltaT can vary based on velocity and cell size you can fix max courant no and OpenFOAM will calculate deltaT automatically.
Regarding documentation on errors, there is no such documentation available but based on your theoretical knowledge and error message you can resolve the issue.

Regards,
Divyesh Variya
25-07-21, 10:19 a.m. divyesh


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