CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   OpenFOAM Running, Solving & CFD (http://www.cfd-online.com/Forums/openfoam-solving/)
-   -   Unknown error when changing turbulence model (http://www.cfd-online.com/Forums/openfoam-solving/124785-unknown-error-when-changing-turbulence-model.html)

babakflame October 13, 2013 03:57

Unknown error when changing turbulence model
 
Dear buddies
I changed my turbulence model from kepsilon to realizableKE
and this error happens during running:

Code:

Starting time loop

Time = 1

DILUPBiCG:  Solving for Ux, Initial residual = 1, Final residual = 1.76289432e-08, No Iterations 6
DILUPBiCG:  Solving for Uy, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG:  Solving for Uz, Initial residual = 0, Final residual = 0, No Iterations 0
GAMG:  Solving for p, Initial residual = 1, Final residual = 0.000958120731, No Iterations 40
time step continuity errors : sum local = 0.0906109149, global = -0.00473111621, cumulative = -0.00473111621
DILUPBiCG:  Solving for H, Initial residual = 0.999999999, Final residual = 1.40752135e-08, No Iterations 9
Updating look-up table extractions...
Updating mass fraction extractions...
DILUPBiCG:  Solving for csi, Initial residual = 1, Final residual = 3.12448826e-08, No Iterations 10
DILUPBiCG:  Solving for csiv2, Initial residual = 1, Final residual = 5.93143858e-09, No Iterations 4
#0  Foam::error::printStack(Foam::Ostream&) in "/home/babak/OpenFOAM/OpenFOAM-2.1.x/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#1  Foam::sigFpe::sigHandler(int) in "/home/babak/OpenFOAM/OpenFOAM-2.1.x/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#2  in "/lib/x86_64-linux-gnu/libc.so.6"
#3  Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/home/babak/OpenFOAM/OpenFOAM-2.1.x/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#4  void Foam::divide<Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/home/babak/OpenFOAM/babak-2.1.x/platforms/linux64GccDPOpt/bin/turbulentFlameletRhoSimplecFoam"
#5  at realizableKE.C:0
#6  Foam::compressible::RASModels::realizableKE::correct() in "/home/babak/OpenFOAM/OpenFOAM-2.1.x/platforms/linux64GccDPOpt/lib/libcompressibleRASModels.so"
#7 
 in "/home/babak/OpenFOAM/babak-2.1.x/platforms/linux64GccDPOpt/bin/turbulentFlameletRhoSimplecFoam"
#8  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#9 
 in "/home/babak/OpenFOAM/babak-2.1.x/platforms/linux64GccDPOpt/bin/turbulentFlameletRhoSimplecFoam"
Floating point exception

would somebody plz hint me what is this error? and how can be fixed?


Regards
Bobi

Lieven October 13, 2013 17:15

Dear Bobi,

This looks like you get a division by 0 in the evaluation of the fields in the turbulence model which (always) throws a Floating Point Exception.

I guess you set the initial value for k and/or epsilon to 0.0. If this is indeed the case, change this to something else. That will most likely solve the issue.

Cheers,

L

babakflame October 13, 2013 23:41

Greetings Lieven

My case works with k-epsilon model. I tried to work with variants solvers and found that GAMG solver and Gauss Seidel smoother make this error when trying to move to for instance kOmegaSST model. I employed PCG abd PBiCG solvers then the problem removed.

Thanks for your hint.

Regards
Bobi


All times are GMT -4. The time now is 17:09.