problem?
 

Hi, everyone.

Now I meet with the problem as follows,

Time = 0.05

smoothSolver: Solving for Ux, Initial residual = 1, Final residual = 0.0610913, No Iterations 2
smoothSolver: Solving for Uy, Initial residual = 1, Final residual = 0.0543365, No Iterations 4
smoothSolver: Solving for Uz, Initial residual = 1, Final residual = 0.0650467, No Iterations 2
GAMG: Solving for p, Initial residual = 1, Final residual = 8.29534e-09, No Iterations 305
time step continuity errors : sum local = 6.87035e-11, global = -3.69711e-13, cumulative = -3.69711e-13
smoothSolver: Solving for epsilon, Initial residual = 0.168528, Final residual = 0.00822444, No Iterations 2
bounding epsilon, min: -1.30591 max: 22.8225 average: 1.34645
smoothSolver: Solving for k, Initial residual = 1, Final residual = 0.0306537, No Iterations 3
bounding k, min: -29.4278 max: 338.848 average: 1.46748
ExecutionTime = 2.98 s ClockTime = 3 s

Time = 0.1

smoothSolver: Solving for Ux, Initial residual = 0.713072, Final residual = 0.0438459, No Iterations 4
smoothSolver: Solving for Uy, Initial residual = 0.215975, Final residual = 0.0171105, No Iterations 2
smoothSolver: Solving for Uz, Initial residual = 0.594642, Final residual = 0.0478476, No Iterations 3
GAMG: Solving for p, Initial residual = 0.597969, Final residual = 9.74486e-09, No Iterations 488
time step continuity errors : sum local = 2.2033e-10, global = -1.97881e-11, cumulative = -2.01578e-11
smoothSolver: Solving for epsilon, Initial residual = 0.0527079, Final residual = 0.00391902, No Iterations 2
bounding epsilon, min: -12.046 max: 2622.6 average: 2.50039
#0 Foam::error::printStack(Foam::Ostream&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#1 Foam::sigFpe::sigHandler(int) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#2 in "/lib64/libc.so.6"
#3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#4 void Foam::divide<Foam::fvPatchField>(Foam::FieldField< Foam::fvPatchField, double>&, Foam::FieldField<Foam::fvPatchField, double> const&, Foam::FieldField<Foam::fvPatchField, double> const&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#5 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::operator/<Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#6 Foam::incompressible::RASModels::realizableKE::cor rect() in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#7
in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/bin/simpleFoam"
#8 __libc_start_main in "/lib64/libc.so.6"
#9
at /home/abuild/rpmbuild/BUILD/glibc-2.15/csu/../sysdeps/x86_64/elf/start.S:116
Gleitkomma-Ausnahme


Can zou help me?

Thanks millions in advance.

Hi,

Your values of k and epsilon become negative. This means that there is a possibility of dividing by zero!

Try start upwinding the divergence terms for k and epsilon and see, if this helps in bounding the values of k and epsilon. Another problem could be your boundary conditions for k and epsilon. I have never worked with this type of turbulence model, but it seems that one has to be careful in order to get a stable solution.

All the best,

Niels