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 am9109 April 4, 2013 05:53

Time step continuity errors

Hello everyone,

I'm currently trying to run sonicFoam but I get the following error, does anyone have an idea about what could be the source of this problem?

Thanks!

Starting time loop

Time = 1e-08

Courant Number mean: 0.00176125 max: 0.0405339
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for Ux, Initial residual = 1, Final residual = 7.76785e-17, No Iterations 1
DILUPBiCG: Solving for Uy, Initial residual = 1, Final residual = 9.40551e-11, No Iterations 2
DILUPBiCG: Solving for e, Initial residual = 1, Final residual = 1.48183e-10, No Iterations 2
DILUPBiCG: Solving for p, Initial residual = 1, Final residual = 1.83804e-16, No Iterations 4
DILUPBiCG: Solving for p, Initial residual = 0.00157704, Final residual = 1.98549e-14, No Iterations 3
DILUPBiCG: Solving for p, Initial residual = 2.68957e-05, Final residual = 6.00475e-13, No Iterations 2
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 1.03078e-16, global = -1.2921e-17, cumulative = -1.2921e-17
DILUPBiCG: Solving for p, Initial residual = 0.00126998, Final residual = 5.04877e-15, No Iterations 3
DILUPBiCG: Solving for p, Initial residual = 1.58899e-05, Final residual = 2.60516e-13, No Iterations 2
DILUPBiCG: Solving for p, Initial residual = 3.59162e-07, Final residual = 5.96198e-15, No Iterations 2
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 9.92037e-17, global = -1.59358e-17, cumulative = -2.88568e-17
#0 Foam::error::printStack(Foam::Ostream&) at ??:?
#1 Foam::sigFpe::sigHandler(int) at ??:?
#2 Uninterpreted:
#3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) at ??:?
#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&) at ??:?
#5 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::operator/<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<doub le, Foam::fvPatchField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) at ??:?
#6 Foam::compressible::RASModels::SpalartAllmaras::ch i() const at ??:?
#7 Foam::compressible::RASModels::SpalartAllmaras::co rrect() at ??:?
#8
at ??:?
#9 __libc_start_main in "/lib/i386-linux-gnu/libc.so.6"
#10
at ??:?

 erichu April 4, 2013 07:23

It looks to me like div by zero in the turbulence model. Maybe try to change relaxation factors. So far I've never used a transient solver in OpenFOAM but Initial residual 0 for rho looks confusing to me.

 giovanidiniz June 26, 2013 09:05

am9109,

I've been trying to setup a propeller in OF using pimpleDyMFoam and I faced the same error message you did.

What I had to do to was to adjust the initial deltaT in my controlDict and allow the solver to adjust it to control the Courant number using