[tH3f0rC3]

Hello,

I have another question to
-k=turbulent energy
-epsilon=dissipation
-nut=turbulent viscosity

I have to set up these files in the 0-file as boundary cinditions.
k and epsilon must have a value for the inlet surfaces. But how can I calculate these values?
And what is meant with the values
Cmu 0.09;
kappa 0.41;
E 9.8;
They are automatically set up as written above.

What do they mean?

Best Regards,
tH3f0rC3

[ang_dipl_ing_fd]

hi dirk,
may be this will help you

http://www.cfd-online.com/Wiki/Turbu...ary_conditions

the other values are default model coefficients which i would not change.

[tH3f0rC3]

Hi,

thank you, that's a very good link! :-)

[tH3f0rC3]

In the description is written that k and epsilon must be specified for the inlet boundaries.
But how do I set up the walls or outlets?

The suggestion of ANSA is to set zeroGradient to walls and outlets. ANSA suggests this by outputting the file as an OpenFoam case. So i don't know if this is right.

Another question is how to set up inlet and outlet layers in nut. For walls I can use nutwallfunction but what shall I use for inlet and outlets.
The suggestion of ANSA in this case is also zeroGradient.

Best Regards,
tH3f0rC3

[ang_dipl_ing_fd]

hi dirk,
i would use for k and epsilon:
...
outlet
{
type inletOutlet;
inletValue $internalField; // or you calculate with estimated values
value $internalField; // only a placeholder
}
...

and for nut:

"(inlet|outlet)" // so you specify inlet AND outlet at the same time
{
type calculated;
}

for walls you can use wall function for k and epsilon
"(wallA|wallB|wallC)"
{
type kqRWallFunction; // wall function for k, q and R
}

and

wall
{
type epsilonWallFunction;
}

This is for incompressible simulation!!!
If you are fluid is compressible than you have to set

type compressible::"Wall_Function";

[derkermit]

Originally Posted by tH3f0rC3

Hi,

is there someone else, who understands the following error message?

Create time
Create mesh for time = 0

Reading g
Reading thermophysical properties
Selecting thermodynamics package hPsiThermo<pureMixture<constTransport<specieThe rmo<hConstThermo<perfectGas>>>>>
#0 Foam::error:rintStack(Foam::Ostream&) in "/data/caehgb.za/studienarbeit-di rk/work/OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7.1/lib/linux64GccDPOpt/libOpenFOA M.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/data/caehgb.za/studienarbeit-dirk/work /OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7.1/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 __restore_rt in "/lib64/tls/libc.so.6"
#3 Foam::hPsiThermo<Foam:ureMixture<Foam::constTran sport<Foam::specieThermo<F oam::hConstThermo<Foam:erfectGas> > > > >::calculate() in "/data/caehgb.za/stu dienarbeit-dirk/work/OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7.1/lib/linux64GccDPO pt/libbasicThermophysicalModels.so"
#4 Foam::hPsiThermo<Foam:ureMixture<Foam::constTran sport<Foam::specieThermo<F oam::hConstThermo<Foam:erfectGas> > > > >::hPsiThermo(Foam::fvMesh const&) in "/data/caehgb.za/studienarbeit-dirk/work/OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7 .1/lib/linux64GccDPOpt/libbasicThermophysicalModels.so"
#5 Foam::basicPsiThermo::addfvMeshConstructorToTable< Foam::hPsiThermo<Foam:ur eMixture<Foam::constTransport<Foam::specieThermo<F oam::hConstThermo<Foam:erfec tGas> > > > > >::New(Foam::fvMesh const&) in "/data/caehgb.za/studienarbeit-dirk /work/OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7.1/lib/linux64GccDPOpt/libbasicTher mophysicalModels.so"
#6 Foam::basicPsiThermo::New(Foam::fvMesh const&) in "/data/caehgb.za/studienar beit-dirk/work/OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7.1/lib/linux64GccDPOpt/lib basicThermophysicalModels.so"
#7 main in "/data/caehgb.za/studienarbeit-dirk/work/OpenFoam_ParaView/OpenFOAM/ OpenFOAM-1.7.1/applications/bin/linux64GccDPOpt/buoyantSimpleRadiationFoam"
#8 __libc_start_main in "/lib64/tls/libc.so.6"
#9 Foam::regIOobject::writeObject(Foam::IOstream::str eamFormat, Foam::IOstream: :versionNumber, Foam::IOstream::compressionType) const in "/data/caehgb.za/studi enarbeit-dirk/work/OpenFoam_ParaView/OpenFOAM/OpenFOAM-1.7.1/applications/bin/li nux64GccDPOpt/buoyantSimpleRadiationFoam"
Floating point exception

I got a similar error a few days ago when solving a heat-transfer-case. I got rid of it by not setting the temperature to 0 K anywhere
Maybe that helps someone...

[Peter88]

You probably have a zero pressure at the internalField. Any how, I got the same message and it went away when I was changing the internal pressure and pressure at outlet.

Gr Peter