[mdeaves]

Hi all!

Using the airFoil2D tutorial as a starting point I am trying to investigate the flow over a NACA0012 using SpallartAlmars turbulence model, wall functions, simpleFoam, and an O-Mesh that was generated in Pointwise.

When I run simpleFoam I get this error,

#0 Foam::error:rintStack(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
at ??:?
#9
at ??:?
#10 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#11
at ??:?
Floating point exception (core dumped)

I can understand enough to know that the solver GAMG is involved with some bad math (divide by zero maybe?), but I can't figure out much more than that. Hopefully you can help me.

My boundary conditions follow post #48 from jferrari on this thread. They are very simple for an O-mesh, only farfield, airfoil, and empty in the z-direction.

One weird thing is that when I use a C-Type mesh that I built using snappyHexMesh simpleFoam runs with no errors. However running the Pointwise O-mesh with the same solver settings and boundary conditions crashes simpleFoam. I have attached some of my case files as well as the log of checkMesh.

Any help is greatly appreciated.

-Michael

[alexeym]

Hi,

You have convergence problem even before GAMG is invoked:

Time = 1

smoothSolver:  Solving for Ux, Initial residual = 1, Final residual = 259.68, No Iterations 1000
smoothSolver:  Solving for Uy, Initial residual = 1, Final residual = 7.08758, No Iterations 1000
...

As you can see, final residual is greater than initial and number of iterations are equal to maxIter.

Also you have got this warning:

--> FOAM Warning : 
    From function Field<Type>::Field(const word& keyword, const dictionary&, const label)
    in file /home/openfoam/OpenFOAM/OpenFOAM-2.3.1/src/OpenFOAM/lnInclude/Field.C at line 318
    Reading "/home/mdeaves/Dropbox/ProjectBoomerang/OpenFOAM/run/airFoil2DSA_Omesh/0/U.boundaryField.farfield" from line 25 to line 26
    expected keyword 'uniform' or 'nonuniform', assuming deprecated Field format from Foam version 2.0.

Can you post your U boundary conditions?

[mdeaves]

Thanks for pointing that out!

I forgot to add 'uniform' in front of the U boundary condition on the farfield. Adding that removed the warning.

Attached is my U file and the new log file. Why would the smoothSolver be blowing up so quickly?

[mdeaves]

Here are my other BC files too.

[wangchengan2003]

Dear Michael Deaves,
Have you solved this problem? I meet the same problem with the mesh by pointwise.
Sincerely
Chengan