[Raza Javed]

Hello Everyone,


I have one rectangular fluid region as you can see in the figure below:


I am using simpleFoam solver and my OpenFoam version is 4.1.


I am copying the case pitzDaily.


First I tried to model the simple laminar flow, and that worked perfectly fine.


Then I changed the flow from laminar to Turbulent.


For that, to increase my Reynold's number, I increased my fluid flow.



I changed the TurbulenceProperties directory, then I changed the k, Epsilon and nut files in the 0 directory.


By keeping other things same, When I RUN the solver, the residuals of velocity don't converge, and also the residuals of k and Epsilon becomes very high (you can see in the error below).

Time = 180

smoothSolver:  Solving for Ux, Initial residual = 0.937013, Final residual = 0.0312575, No Iterations 2
smoothSolver:  Solving for Uy, Initial residual = 0.911587, Final residual = 0.0381164, No Iterations 2
smoothSolver:  Solving for Uz, Initial residual = 0.995563, Final residual = 0.0335498, No Iterations 2
GAMG:  Solving for p, Initial residual = 2.90637e-23, Final residual = 2.90637e-23, No Iterations 0
time step continuity errors : sum local = 1.47055e+32, global = 1.9861e+20, cumulative = 2.28806e+20
smoothSolver:  Solving for epsilon, Initial residual = 9.32529e-09, Final residual = 6.42063e-10, No Iterations 2
bounding epsilon, min: -1.42797e+48 max: 1.74595e+52 average: 5.31265e+47
smoothSolver:  Solving for k, Initial residual = 1, Final residual = 0.0858033, No Iterations 9
bounding k, min: -2.40503e+43 max: 9.54428e+48 average: 9.45471e+44
ExecutionTime = 213.94 s  ClockTime = 215 s

Time = 181

smoothSolver:  Solving for Ux, Initial residual = 0.003325, Final residual = 0.000299627, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0.01712, Final residual = 0.000743184, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 0.0332767, Final residual = 0.00204101, No Iterations 1
#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2  ? in "/lib/x86_64-linux-gnu/libc.so.6"
#3  Foam::GAMGSolver::scale(Foam::Field<double>&, Foam::Field<double>&, Foam::lduMatrix const&, Foam::FieldField<Foam::Field, double> const&, Foam::UPtrList<Foam::lduInterfaceField const> const&, Foam::Field<double> const&, unsigned char) const at ??:?
#4  Foam::GAMGSolver::Vcycle(Foam::PtrList<Foam::lduMatrix::smoother> const&, Foam::Field<double>&, Foam::Field<double> const&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::PtrList<Foam::Field<double> >&, Foam::PtrList<Foam::Field<double> >&, unsigned char) const at ??:?
#5  Foam::GAMGSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
#6  Foam::fvMatrix<double>::solveSegregated(Foam::dictionary const&) at ??:?
#7  Foam::fvMatrix<double>::solve(Foam::dictionary const&) at ??:?
#8  Foam::fvMatrix<double>::solve() at ??:?
#9  ? at ??:?
#10  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#11  ? at ??:?
Floating point exception (core dumped)

I don't know what mistake I am doing.


Can someone please help me out in this? If you need any further information about the case, I would be happy to provide that.


Thank you

[kishpishar]

It's difficult to know the reason from this picture. If you could post your case, I can take a look.

[lpz456]

Hello, have solve your problem? I think epsilon-based models require more demanding numreical schemes than omega-based model