I recieve this error when I execute pisoFoam:
Time = 0.00142
Courant Number mean: 3.72507e+52 max: 1.36418e+54
DILUPBiCG: Solving for Ux, Initial residual = 0.555198, Final residual = 1.81207e-06, No Iterations 35
DILUPBiCG: Solving for Uy, Initial residual = 0.882337, Final residual = 2.82071e-06, No Iterations 36
DILUPBiCG: Solving for Uz, Initial residual = 0.959453, Final residual = 2.3849e-06, No Iterations 29
DICPCG: Solving for p, Initial residual = 0.685706, Final residual = 0.0341773, No Iterations 70
time step continuity errors : sum local = 2.65701e+50, global = 1.48284e+49, cumulative = 1.38529e+49
DICPCG: Solving for p, Initial residual = 0.684507, Final residual = 9.50829e-07, No Iterations 171
time step continuity errors : sum local = 2.06627e+46, global = -1.52172e+44, cumulative = 1.38528e+49
DILUPBiCG: Solving for k, Initial residual = 0.88271, Final residual = 7.51988e-06, No Iterations 6
bounding k, min: -3.72039e+117 max: 7.6031e+117 average: 2.9493e+116
ExecutionTime = 164.59 s ClockTime = 165 s
Time = 0.00143
Courant Number mean: 8.88307e+51 max: 2.84151e+53
DILUPBiCG: Solving for Ux, Initial residual = 0.856534, Final residual = 7.94225e-06, No Iterations 39
DILUPBiCG: Solving for Uy, Initial residual = 0.826641, Final residual = 9.82446e-06, No Iterations 37
DILUPBiCG: Solving for Uz, Initial residual = 0.6356, Final residual = 6.89001e-06, No Iterations 35
DICPCG: Solving for p, Initial residual = 0.702043, Final residual = 0.0343882, No Iterations 78
time step continuity errors : sum local = 6.28092e+51, global = -2.13804e+49, cumulative = -7.5276e+48
DICPCG: Solving for p, Initial residual = 0.778709, Final residual = 8.64955e-07, No Iterations 171
time step continuity errors : sum local = 5.07704e+47, global = -7.17519e+44, cumulative = -7.52832e+48
#0 Foam::error::printStack(Foam::Ostream&) in "/opt/OpenFOAM/OpenFOAM-1.6/lib/linux64GccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/opt/OpenFOAM/OpenFOAM-1.6/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 ?? in "/lib/libc.so.6"
#3 Foam::PBiCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/opt/OpenFOAM/OpenFOAM-1.6/lib/linux64GccDPOpt/libOpenFOAM.so"
#4 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/opt/OpenFOAM/OpenFOAM-1.6/lib/linux64GccDPOpt/libfiniteVolume.so"
#5 Foam::incompressible::LESModels::oneEqEddy::correc t(Foam::tmp<Foam::GeometricField<Foam::Tensor<doub le>, Foam::fvPatchField, Foam::volMesh> > const&) in "/opt/OpenFOAM/OpenFOAM-1.6/lib/linux64GccDPOpt/libincompressibleLESModels.so"
#6 Foam::incompressible::LESModel::correct() in "/opt/OpenFOAM/OpenFOAM-1.6/lib/linux64GccDPOpt/libincompressibleLESModels.so"
#7 main in "/opt/OpenFOAM/OpenFOAM-1.6/applications/bin/linux64GccDPOpt/pisoFoam"
#8 __libc_start_main in "/lib/libc.so.6"
#9 _start at /usr/src/packages/BUILD/glibc-2.9/csu/../sysdeps/x86_64/elf/start.S:116
It's running for a while and then it crashes.
Could it be, that my Courant Number is much to hight? Or isn't there enough memory?
Have I nice weekend,
PS: I'll only be back on monday :-)
Yes, your simulations are diverging and the Courant number gets way out of hand. As usual, check your boundary and initial conditions, and then your numerical parameters. Time step looks like it's pretty small already, so I'm assuming that's not your problem.
thx for your help.
The courant number depends on the speed, the timestep and the cell size, right? But how can I improve the courant number? I have already tried even smaler time steps and also a smaler inital speed U, but with the same result.
What else could I do to make the calculation converging?
About your case, it would be useful to know some more details on the case and the numerical setup (fvSchemes, essentially).
Thank you very much, I really appreciate your help!
My case is about a pipe flow with a tube in the middle.
This is my fvSchemes file:
There are the initial conditions for U:
Sorry for the long post.
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