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-   -   nutSpalartAllmarasWallFunction (http://www.cfd-online.com/Forums/openfoam/75283-nutspalartallmaraswallfunction.html)

chelvistero April 21, 2010 06:56

nutSpalartAllmarasWallFunction
 
Hello Foamers,
I'd like to simulate a near wall treatment with simpleFoam. In other threads I have read that there is the possibiltity to simulate KOmegaSST with near wall treatment using nutSpalartAllmarasWallFunction in the nut file. In the k -file I use kqRWallFunction and in the omega - file I use omegaWallFunction. But using this I always get a failure message. Does anybody know how to fix this?

Thank you in advance

Failure message:

Reading/calculating face flux field phi

Selecting incompressible transport model Newtonian
Selecting RAS turbulence model kOmegaSST
#0 Foam::error::printStack(Foam::Ostream&) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libOpenFOAM.so"
#2 Uninterpreted:
#3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libOpenFOAM.so"
#4 Foam::operator/(Foam::tmp<Foam::Field<double> > const&, Foam::UList<double> const&) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libOpenFOAM.so"
#5 Foam::incompressible::RASModels::nutSpalartAllmara sWallFunctionFvPatchScalarField::calcNut() const in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libincompressibleRASModels.so"
#6 Foam::incompressible::RASModels::nutWallFunctionFv PatchScalarField::updateCoeffs() in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libincompressibleRASModels.so"
#7 Foam::fvPatchField<double>::evaluate(Foam::Pstream ::commsTypes) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/applications/bin/linuxGccDPOpt/simpleFoam"
#8 Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>::GeometricBoundaryField::evaluate() in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/applications/bin/linuxGccDPOpt/simpleFoam"
#9 Foam::incompressible::RASModels::kOmegaSST::kOmega SST(Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::transportModel&) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libincompressibleRASModels.so"
#10 Foam::incompressible::RASModel::adddictionaryConst ructorToTable<Foam::incompressible::RASModels::kOm egaSST>::New(Foam::GeometricField<Foam::Vector<dou ble>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::transportModel&) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libincompressibleRASModels.so"
#11 Foam::incompressible::RASModel::New(Foam::Geometri cField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::transportModel&) in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/lib/linuxGccDPOpt/libincompressibleRASModels.so"
#12 main in "/home/axel/OpenFOAM/OpenFOAM-1.6.x/applications/bin/linuxGccDPOpt/simpleFoam"
#13 __libc_start_main in "/lib/tls/i686/cmov/libc.so.6"
#14 _start at /build/buildd/eglibc-2.10.1/csu/../sysdeps/i386/elf/start.S:122
Floating point exception

chelvistero April 22, 2010 04:24

Is there a simple possibility to simulate a turbolent flow without any wall functions? And what bc's are necessary to do this? I would be very happy about help.

Thank you in advance

florian_krause April 22, 2010 04:47

Hi Axel,

you can simulate a turbulent flow without any wall functions, by DNS, LES or RANS with a low-Re turbulence model. From your previous post, I assume you want to perform RANS calculations, right?! OpenFOAM offers different low-Re RANS turbulence models. I only have experience with the LaunderSharmaKE model, for which I set:

epsilon at the wall:
zeroGradient

k at the wall:
type fixedValue;
value uniform 1e-10;

your first grid point normal to the wall should have y+ < 1 in order to resolve the wall!

good luck!
Florian

chelvistero April 22, 2010 04:54

Thank you for your fast reply. I will try it out immediatly!!!

bastil April 22, 2010 16:53

I ran into the same problems with nutSpalartAllmarasWallFUnction. I still hold the opinion it should work but I don't know how.

chelvistero April 23, 2010 03:55

Hello Bastil,
when you are using OpenFoam 1.6.x check the updates. I just updated and now it worked. But there is no yPlus output. Do you know if it is advisable to check the yPlus value first with nutWallFunction and after that to turn to nutSpalartAllmarasWallFunction?

Now I have try to simulate with nutSpalartAllmarasWallFunction but the results are not so good i hoped for. For k I used fixedValue 1e-10 and for omega i used 1.zeroGradient
and 2. omegaWallFunction uniform 0 . Has anybody experience with this kind of lowRe Simulation? And are the boundaries correct?
I would be very happy about answers and suggestions!!


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