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-   -   simpleFoam error - calculation stopped (http://www.cfd-online.com/Forums/openfoam/79958-simplefoam-error-calculation-stopped.html)

RugbyGandalf September 9, 2010 09:56

simpleFoam error - calculation stopped
 
1 Attachment(s)
hello,

i tried to calculate the flow through two combined cylinders...
meshing tool was netgen.
it is one of the example geometries of netgen...

but simpleFoam solver always breaks the operation after 23 steps of calculation.
it points out the following errors in the terminal windows:

#0 Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam170/lib/linux64GccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/opt/openfoam170/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 in "/lib/libc.so.6"
#3 Foam::PBiCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/opt/openfoam170/lib/linux64GccDPOpt/libOpenFOAM.so"
#4 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/opt/openfoam170/lib/linux64GccDPOpt/libfiniteVolume.so"
#5 Foam::lduMatrix::solverPerformance Foam::solve<double>(Foam::tmp<Foam::fvMatrix<doubl e> > const&) in "/opt/openfoam170/lib/linux64GccDPOpt/libincompressibleRASModels.so"
#6 Foam::incompressible::RASModels::kEpsilon::correct () in "/opt/openfoam170/lib/linux64GccDPOpt/libincompressibleRASModels.so"
#7
in "/opt/openfoam170/applications/bin/linux64GccDPOpt/simpleFoam"
#8 __libc_start_main in "/lib/libc.so.6"
#9
in "/opt/openfoam170/applications/bin/linux64GccDPOpt/simpleFoam"
Floating point exception


could someone help me, how to get this case run?

i also postet the "0" time directory and system folder
constant folder was a bit to large :(

thank you very much in advance :)

Martin

keul September 9, 2010 10:29

Hi,

I can have a look at your problem but I need your constant folder. You could reduce the folder size if you delete all the files in polymesh exept the blockMeshDict file.

RugbyGandalf September 9, 2010 10:46

thank you very much...

but i do not have a blockmesh file...

the mesh was created by netgen...

but of course i could send it via email, if that would be okay..!?

keul September 9, 2010 10:50

No problem!

keul September 9, 2010 10:59

I sended you my mail by private message.

keul September 10, 2010 03:43

Hi RugbyGandalf!

I launched your case with epsilon = 1 and it works fine. When you work with a turbulent model the solution convergence depends a lot of your initial conditions on k and epsilon. So maybe try other values until you find good ones.

Good luck!

RugbyGandalf September 10, 2010 03:59

thank you very much :)

it is working great :)

is there a "rule" for setting epsilon and k?

what are these values saying exactly?
i am very new to cfd and openFoam - so i do not already know about all the values :(

keul September 10, 2010 04:30

I'm not an expert in turbulent model but k and epsilon depend of initial velocity, characteristic length and Reynolds number. Maybe you should have a look at some explanations you could find on Wikipedia to fix your initial conditions.


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