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Flointing point error also for a tutorial example

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Old   May 9, 2011, 10:18
Default Flointing point error also for a tutorial example
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Hi,

I receive each time "Flointing point error" and I really don't know what to do anymore... I have to simulate a sandstorm - I tried to use the damBreak case from tutorials - I found another tutorial that develops this case - actually it changes only the geometry (it describes in blockMeshDict a bottle):
http://www.tfd.chalmers.se/~hani/kurser/OS_CFD_2007/HassanHemida/Hassan_Hemida_VOF.pdf

I followed step by step what is there but when I apply the interFoam solver I receive tha Floining point error. For this tutorial I didn't change anything...

I worked before with another example - also begining from a tutorial (snowDrift example) and also I received the same error. I only changed the geometry and I generated other mesh.

Here are the last line from my output (first example with interFoam):
DICPCG: Solving for p_rgh, Initial residual = 0.853222, Final residual = 0.033701, No Iterations 20
time step continuity errors : sum local = 5.5888e-05, global = -8.29502e-06, cumulative = -0.0040989
DICPCG: Solving for p_rgh, Initial residual = 0.646448, Final residual = 0.0242661, No Iterations 27
time step continuity errors : sum local = 0.000127955, global = 4.05392e-05, cumulative = -0.00405836
DICPCG: Solving for p_rgh, Initial residual = 0.971427, Final residual = 7.87579e-08, No Iterations 260
time step continuity errors : sum local = 1.40968e-09, global = 4.77194e-13, cumulative = -0.00405836
ExecutionTime = 7.13 s ClockTime = 8 s

Courant Number mean: 0.205508 max: 417.869
Interface Courant Number mean: 0.000488175 max: 2.15027
#0 Foam::error:rintStack(Foam::Ostream&) in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#2 Uninterpreted:
#3 Foam::Time::adjustDeltaT() in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#4 Foam::Time::setDeltaT(double) in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#5
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/interFoam"
#6 __libc_start_main in "/lib/libc.so.6"
#7
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/interFoam"

I really don't know what do anymore - I'm beginer to OpenFoam and I tryed many ways - to redefine geometry, to refine the mesh and so on. I just want to make a very very simple example but I receive this error always.

Cristina
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Old   May 9, 2011, 10:24
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Bernhard
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Changes in the geometry can cause large differences in the physics and thus the results. Suppose you increase the size of the dam break case by a factor 100.

In your case the Courant number grows to large. This suggests to reduce the time step. (More info on Courant number can be found all around these forums)
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Old   May 9, 2011, 12:48
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Andrea Pasquali
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Hi Cristina,

Did you calculate your Time step? It's max velocity e min cell size function. You can find the formula in OpenFOAM user guide.

Did you have those rows in your controlDict?
Quote:
adjustTimeStep yes;
maxCo 0.9;
maxAlphaCo 0.5;
maxDeltaT 0.01;
They fix the Co and ensure you to run with the max time step allowable.

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Old   May 9, 2011, 12:59
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I have so:

adjustTimeStep yes;

maxCo 0.5;
maxAlphaCo 0.5;

maxDeltaT 1;

and I receive Flointing point error. I set the maxCo to 0.2 and it worked...

I didn.t knowo about this formula ... Number of cells when I have:
"hex (3 2 1 0 17 16 15 14) (50 5 1) simpleGrading (1 1 1)"

is 50 x 5 x 1?

Cristina
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Old   May 9, 2011, 14:33
Default After much time still error
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Even with maxCo = 0.2 I receive this error but after much, much time:

Time = 0.0012026223658074956

MULES: Solving for alpha1
Liquid phase volume fraction = 0.00114771 Min(alpha1) = -4.86666e-05 Max(alpha1) = 1
MULES: Solving for alpha1
Liquid phase volume fraction = 0.00114779 Min(alpha1) = -4.86559e-05 Max(alpha1) = 1
#0 Foam::error:rintStack(Foam::Ostream&) in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#2 Uninterpreted:
#3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/opt/openfoam170/lib/linuxGccDPOpt/libOpenFOAM.so"
#4 void Foam::divide<Foam::fvsPatchField, Foam::surfaceMesh>(Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh>&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&) in "/opt/openfoam170/applications/bin/linuxGccDPOpt/interFoam"
#5 Foam::tmp<Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> > Foam:perator/<Foam::fvsPatchField, Foam::surfaceMesh>(Foam::tmp<Foam::GeometricField< double, Foam::fvsPatchField, Foam::surfaceMesh> > const&, Foam::tmp<Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> > const&) in "/opt/openfoam170/lib/linuxGccDPOpt/libincompressibleTransportModels.so"
#6 Foam::fv::ddtScheme<Foam::Vector<double> >::fvcDdtPhiCoeff(Foam::GeometricField<Foam::Vecto r<double>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&) in "/opt/openfoam170/lib/linuxGccDPOpt/libfiniteVolume.so"
#7 Foam::fv::EulerDdtScheme<Foam::Vector<double> >::fvcDdtPhiCorr(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> const&) in "/opt/openfoam170/lib/linuxGccDPOpt/libfiniteVolume.so"
#8
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/interFoam"
#9
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/interFoam"
#10 __libc_start_main in "/lib/libc.so.6"
#11
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/interFoam"
Floating point exception
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