[alberto]

Description: The forwardStep tutorial of sonicFoam doesn't complete the simulation and aborts with the error:

Courant Number mean: -8.55342e+25 max: 1.66084e+28
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
#0 Foam::error::printStack(Foam:stream&)
#1 Foam::sigFpe::sigFpeHandler(int)
#2 Uninterpreted: [0xffffe420]
#3 Foam::DILUPreconditioner::DILUPreconditioner(Foam: :lduMatrix::solver const&, Foam::Istream&)
#4 Foam::lduMatrix::preconditioner::addasymMatrixCons tructorToTable<foam::dilupreco nditioner>::New(Foam::lduMatrix::solver const&, Foam::Istream&)
#5 Foam::lduMatrix::preconditioner::New(Foam::lduMatr ix::solver const&, Foam::Istream&)
#6 Foam::PBiCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const
#7 Foam::fvMatrix<foam::vector<double> >::solve(Foam::Istream&)
#8 Foam::lduMatrix::solverPerformance Foam::solve<foam::vector<double> >(Foam::tmp<foam::fvmatrix<foam::vector<double> > > const&)
#9 main
#10 __libc_start_main
#11 __gxx_personality_v0 at ../sysdeps/i386/elf/start.S:122

Increasing the time step to 0.003s circumvents the problem.

Solver/Application: sonicFoam

Source file:

Testcase: forwardStep tutorial for sonicFoam

Platform: All

Version: 1.4

Notes: The issue was found by Florian Fruth. See http://www.cfd-online.com/cgi-bin/Op...how.cgi?1/4657

Regards,
Alberto

[alberto]

As suggested by Hrvoje, the solution consists in setting the outlet BC to zeroGradient for T and U.

I attach the corrected tutorial case.

forwardStep.zip

Regards,
A.