[AndyM]

Hi Foamers,

Ive been using OpenFOAM for nearly a year with moderate success but Ive encountered an issue using the compressible solvers. Ive create a mesh using snappyhexmesh ~1.65million cells which runs fine using simpleFoam. Its a rectangular mesh around a rocket.

My issue is that once transferred to any compressible solvers (ive tried this in 1.4.1, 1.6 and 1.7 with the same mesh) I get errors during the initialisation. Unfortunately I cannot post my mesh on here its ~500mb but the yPlus has an average of 54 and i'm happy with it- i dont believe the erros stem from it.

The latest error I've got is: (using rhoSonicFoam & kOmegaSST on 1.7.0)

Create time

Create mesh for time = 2

Reading thermodynamicProperties

Reading field p

Reading field T

Reading field U

#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 void Foam::divide<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<Foam::Vector<d ouble>, Foam::fvPatchField, Foam::volMesh>&, Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/opt/openfoam170/applications/bin/linuxGccDPOpt/rhoSonicFoam"
#4 Foam::tmp<Foam::GeometricField<Foam::Vector<double >, Foam::fvPatchField, Foam::volMesh> > Foam:perator/<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<Foam::Vector<d ouble>, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/opt/openfoam170/applications/bin/linuxGccDPOpt/rhoSonicFoam"
#5
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/rhoSonicFoam"
#6 __libc_start_main in "/lib/tls/i686/cmov/libc.so.6"
#7
in "/opt/openfoam170/applications/bin/linuxGccDPOpt/rhoSonicFoam"
Floating point exception

All the errors follow a similar theme of aborting at either reading U or selecting the turbulence model (rhoSimple in 1.6 and 1.4.1), and ending with "Floating point exception".

I have a feeling its to do with my BC but I cannot find anything wrong with them.
Here are my BC (please note I only just put the wall functions on k and omega to see if it would make a difference... it didnt):

k
dimensions [0 2 -2 0 0 0 0];

internalField uniform 0.09375;

boundaryField
{
inlet
{
type fixedValue;
value uniform 0.09375;
}

outlet
{
type zeroGradient;
}

sighter_SIGHTER_BLUNT_ASSEM
{
type kqRWallFunction;
value uniform 0.559;
}

top
{
type symmetryPlane;
}

base
{
type symmetryPlane;
}
}

Omega
dimensions [0 0 -1 0 0 0 0];

internalField uniform 0.559;

boundaryField
{
inlet
{
type fixedValue;
value uniform 0.559;
}

outlet
{
type zeroGradient;
}

sighter_SIGHTER_BLUNT_ASSEM
{
type kqRWallFunction;
value uniform 0.559;
}

top
{
type symmetryPlane;
}

base
{
type symmetryPlane;
}
}

p

dimensions [0 2 -2 0 0 0 0];

internalField uniform 0;

boundaryField
{
inlet
{
type zeroGradient;
}

outlet
{
type fixedValue;
value uniform 0;
}

sighter_SIGHTER_BLUNT_ASSEM
{
type zeroGradient;
}

top
{
type symmetryPlane;
}

base
{
type symmetryPlane;
}
}

U

dimensions [0 1 -1 0 0 0 0];

internalField uniform (0 0 0);

boundaryField
{

inlet
{
type fixedValue;
value uniform (0 -50 0);
}
outlet
{
type zeroGradient;
}

sighter_SIGHTER_BLUNT_ASSEM
{
type fixedValue;
value uniform (0 0 0);
}

top
{
type symmetryPlane;
}

base
{
type symmetryPlane;
}
}

nut

dimensions [0 2 -1 0 0 0 0];

internalField uniform 0;

boundaryField
{
inlet
{
type calculated;
value uniform 0;
}
outlet
{
type calculated;
value uniform 0;
}

sighter_SIGHTER_BLUNT_ASSEM
{
type nutWallFunction;
value uniform 0;
}

top
{
type symmetryPlane;
}

base
{
type symmetryPlane;
}

Any ideas would be great.

Thanks in advance
Andrew

[nileshjrane]

Try initializing everything with non-zero value. I see that your pressure and velocity is set to zero in "internalfield".

[AndyM]

Thanks for that. You were right, changing pressure and velocity fixed it all up!

Andrew