simpleFoam bounding and time step continuity errors
Quite new to OF so hope I can find some help here........!
I'm trying to run a simpleFoam case on an aerofoil which I am meshing progressively finer and finer with gmsh. I am having trouble, however, seemingly when the mesh gets to a particular level of fineness.....
I am using the spalmart-allmaras model.
The timestep continuity errors shoot up massively as does the bounding of nuTilda (negative value). This is causing an exception error...
I'm also getting a similar problem in another case using k-epsilon modelling, where the bounding of epsilon and k is similarly negative and very large (again occuring when the mesh becomes fine enough).
Here is my fvSchemes file
Can anyone give me any hints/comments?
I would apply a limiter to the gradients: cellLimited Gauss linear 1; On unstructured grids, use least-squares.
Also, you might want to check your under-relaxation factors for the variables that become unbounded.
I have tried changing my gradSchemes to
I've also tried reducing the relaxation factor for nuTilda (I think this is the correct thing to do but would welcome comments on why). I have
I am still getting the same error though..... here is an excerpt
And then it crashes with the exception error......
Hope you can help
Does the code run without problems if you turn off the turbulence model? It seems none of the equations is converging. I would start checking the setup of the boundary conditions, the mesh quality (checkMesh), ...
Hi alberto, thanks once again for the help!
I've tried running without the turbulence model and it appears I am having problems with my mesh... checkMesh turns up this error
I will continue to investigate but would welcome any comments
I seem to be getting a problem with undefined faces in OF when using gmshToFoam which I think is causing problems later on....
Would it be possible for you to take a look at my .geo file and see what you think - I'm not sure if you're familiar with gmsh but I can't spot any problems...
I am not very familiar with gmsh, sorry.
time step continuity errors
same type of problem i am facing
Time = 63
smoothSolver: Solving for Ux, Initial residual = 0.407445, Final residual = 6.2409e-06, No Iterations 48
smoothSolver: Solving for Uy, Initial residual = 0.713688, Final residual = 8.41503e-06, No Iterations 40
GAMG: Solving for p, Initial residual = 1, Final residual = 0.281817, No Iterations 1000
time step continuity errors : sum local = 5.16688e+27, global = -3.34408e+27, cumulative = -3.34408e+27
smoothSolver: Solving for epsilon, Initial residual = 0.113747, Final residual = 5.51399e-06, No Iterations 2
bounding epsilon, min: -1.00648e+42 max: 2.17508e+52 average: 8.0165e+49
smoothSolver: Solving for k, Initial residual = 4.4491e-10, Final residual = 4.4491e-10, No Iterations 0
ExecutionTime = 30.43 s ClockTime = 31 s
Time = 64
smoothSolver: Solving for Ux, Initial residual = 0.00072263, Final residual = 0.000301801, No Iterations 1000
smoothSolver: Solving for Uy, Initial residual = 0.00426629, Final residual = 0.000911303, No Iterations 1000
#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::lduMa trix::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::dict ionary 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)
how did you solve it?
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