[wang219910611]

Hi Everyone,

I am a newbee with Openfoam and I am currently trying to get familiar with it with its tutorial. (Many bugs happened by the way..)

Something strange happened. I have run sprayFoam and everything is fine. But when I run ./Allrun in the cavitatingFoam case, the log file showed errors as following:

#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 Foam::fvMatrix<double>::solveSegregated(Foam::dict ionary const&) at ??:?
#7 Foam::fvMatrix<double>::solve(Foam::dictionary const&) at ??:?
#8 Foam::SolverPerformance<double> Foam::solve<double>(Foam::tmp<Foam::fvMatrix<doubl e> > const&) at ??:?
#9 Foam::incompressible::RASModels::kOmegaSST::correc t() at ??:?
#10
at ??:?
#11 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#12
at ??:?
Floating point exception (core dumped)

Can anyone offer any advice about this? Your help will be appreciated. : )

[alexeym]

Hi,

I guess you're talking about tutorials/multiphase/cavitatingFoam/ras/throttle case (as there are several cases). The case is quite strange starting with 5-element vector for dimensions (now it should be 7-element vector or symbolic expression, so I guess this case was copied from older versions of OpenFOAM without verification), ending with this sigFpe.

I was able to execute the case (though don't know whether results are meaningful or not) if I change linear system solver for U/k/omega from smoothSolver to PBiCG, i.e. I change fvSolution to:

    "(U|k|omega)"
    {
        solver          PBiCG;
        preconditioner  DILU;
        tolerance       1e-8;
        relTol          0.1;
    /*
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-08;
        relTol          0.1;
    */
    }

    "(U|k|omega)Final"
    {
        $U;
        relTol          0;
    /*
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-08;
        relTol          0;
    */
    }

[wang219910611]

Originally Posted by alexeym

Hi,

I guess you're talking about tutorials/multiphase/cavitatingFoam/ras/throttle case (as there are several cases). The case is quite strange starting with 5-element vector for dimensions (now it should be 7-element vector or symbolic expression, so I guess this case was copied from older versions of OpenFOAM without verification), ending with this sigFpe.

I was able to execute the case (though don't know whether results are meaningful or not) if I change linear system solver for U/k/omega from smoothSolver to PBiCG, i.e. I change fvSolution to:

    "(U|k|omega)"
    {
        solver          PBiCG;
        preconditioner  DILU;
        tolerance       1e-8;
        relTol          0.1;
    /*
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-08;
        relTol          0.1;
    */
    }

    "(U|k|omega)Final"
    {
        $U;
        relTol          0;
    /*
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-08;
        relTol          0;
    */
    }

Hi Alexeym,

Thanks for the kind reply. I have followed your suggestion and the case runs out well. About the dimensions, I have checked through the source file, and found out several vectors in 5-element, and the rest in 7-element.
However, the result seemed a bit strange to me. The nozzle flow is super-cavitating all the way to the end. I am wonder if this is the right calculation.

Regards

Bo

[alexeym]

Originally Posted by wang219910611

However, the result seemed a bit strange to me. The nozzle flow is super-cavitating all the way to the end. I am wonder if this is the right calculation.

Well, there are two ways to check correctness of the calculations:

1. Find a published paper with results and try to reproduce them

2. Find author of the tutorial case and ask him about results

As I'm neither a specialist in cavitation, nor a user of cavitatingFoam, I can only suggest technical things to make the case running.

[wang219910611]

Originally Posted by alexeym

Well, there are two ways to check correctness of the calculations:

1. Find a published paper with results and try to reproduce them

2. Find author of the tutorial case and ask him about results

As I'm neither a specialist in cavitation, nor a user of cavitatingFoam, I can only suggest technical things to make the case running.

I think I can try to compare the results with some papers. Thanks for the quick reply and suggestion. : D