simpleFoam with Launder-Sharma Model
I'm a new user with openfoam. Now i want to use simpleFoam with Launder-Sharma Low-Re Model. There's only one time step calculated. Then a erro as below is displayed.
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create mesh for time = 0
Reading field p
Reading field U
Reading/calculating face flux field phi
Selecting incompressible transport model Newtonian
Selecting RAS turbulence model LaunderSharmaKE
Starting time loop
Time = 0.1
DILUPBiCG: Solving for Ux, Initial residual = 1, Final residual = 0.0606568, No Iterations 1
DILUPBiCG: Solving for Uy, Initial residual = 0.995352, Final residual = 0.0222388, No Iterations 1
DICPCG: Solving for p, Initial residual = 1, Final residual = 0.00735996, No Iterations 6
DICPCG: Solving for p, Initial residual = 0.00365507, Final residual = 3.33199e-05, No Iterations 63
DICPCG: Solving for p, Initial residual = 2.37913e-05, Final residual = 8.92903e-07, No Iterations 30
time step continuity errors : sum local = 4.57548e-05, global = -4.42317e-06, cumulative = -4.42317e-06
#0 Foam::error::printStack(Foam::Ostream&) in "/usr/local/OpenFOAM/1.6/lib/linux64GccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/usr/local/OpenFOAM/1.6/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 __restore_rt at sigaction.c:0
#3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/usr/local/OpenFOAM/1.6/lib/li
#4 void Foam::divide<Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&, Foam::sh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/usr/local/OpenFOAM/1.6/lib/linux64GccDPO
#5 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::operator/<Foam::fvPatchField, Foam::volMeshField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/usr/local/OpenFOAM/1
#6 Foam::incompressible::RASModels::LaunderSharmaKE:: correct() in "/usr/local/OpenFOAM/1.6/lib/linux64GccDPOpt/libincompressible
#7 main in "/usr/local/OpenFOAM/1.6/applications/bin/linux64GccDPOpt/simpleFoam"
#8 __libc_start_main in "/lib64/libc.so.6"
#9 _start at /usr/src/packages/BUILD/glibc-2.9/csu/../sysdeps/x86_64/elf/start.S:116
I cann't get any useful information from the erro.
The p, U, k, nut, epsilon are gaven as boundary condition.
My question is, can simpleFoam be used with LS Model or did I do something wrong?
simpleFoam is able to use LaunderSharma,
look at following posting:
You must be careful with your inlet bc's for k and epsilon.
Thanks for the reply.
why cannot i set the k and epsilon not equal 0 for the boundary condition at wall? That was the problem of me.
I think you are not allowed to divide through zero.
why would you set non-zero values at solid walls for k and epsilon? Launder-Sharma turbulence model is so called "low reynolds number" closure ad its damping function, values of constants, etc. are derived on the basis of zero values for k and epsilon (at solid walls)!
I really suggest that you grab your hands on the following book David C. Wilcox, Turbulence Modelling For CFD
that's what i thought and what i did, set k and epsilon at solid wall equal 0. Then the error as i've replayed in the beginning occurred. As Thomas said, it's a problem of dividing through zero.
I'm a new user in OpenFoam. I appreciate your helps and tips and I'm gratefull for that. My problem is incompressible flow through radial diffuser with low Reynolds number. I want to use LaunderSharmaKE turb. model without wall functions.
1) I deleted nut file and k and epsilon files were setted with fixedValue for wall boundary conditions. The k and epsilon values on the wall I fixed with zero and close to zero (1e-10). In these two situations floting point exception ocurred.
2) Can someone check my attachement files to find out if I made a mistake?
3) I don't understand what "value" below Intensity really does mean. The value of turb. kinetic energy (k) will be calculated based on turb. intensity, so why set this value? Please, can someone clear it me?
value uniform 0.3;
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