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-   -   Problem using atmBoundaryLayerInletVelocity (http://www.cfd-online.com/Forums/openfoam-programming-development/113881-problem-using-atmboundarylayerinletvelocity.html)

bigzakk February 28, 2013 10:21

Problem using atmBoundaryLayerInletVelocity
 
Hi all,

I am trying to use atmBoundaryLayerInletVelocity for a very simple application however I am receiving this error i cant figure out. Thanks for any helps however small

Create time

Create mesh for time = 0

Reading field p

Reading field U

#0 Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam211/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#1 Foam::sigFpe::sigHandler(int) in "/opt/openfoam211/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#2 in "/lib/x86_64-linux-gnu/libc.so.6"
#3 log in "/lib/x86_64-linux-gnu/libm.so.6"
#4 Foam::incompressible::atmBoundaryLayerInletVelocit yFvPatchVectorField::atmBoundaryLayerInletVelocity FvPatchVectorField(Foam::fvPatch const&, Foam::DimensionedField<Foam::Vector<double>, Foam::volMesh> const&, Foam::dictionary const&) in "/opt/openfoam211/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#5 Foam::fvPatchField<Foam::Vector<double> >::adddictionaryConstructorToTable<Foam::incompres sible::atmBoundaryLayerInletVelocityFvPatchVectorF ield>::New(Foam::fvPatch const&, Foam::DimensionedField<Foam::Vector<double>, Foam::volMesh> const&, Foam::dictionary const&) in "/opt/openfoam211/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#6 Foam::fvPatchField<Foam::Vector<double> >::New(Foam::fvPatch const&, Foam::DimensionedField<Foam::Vector<double>, Foam::volMesh> const&, Foam::dictionary const&) in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
#7 Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>::GeometricBoundaryField::GeometricB oundaryField(Foam::fvBoundaryMesh const&, Foam::DimensionedField<Foam::Vector<double>, Foam::volMesh> const&, Foam::dictionary const&) in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
#8 Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>::readField(Foam::dictionary const&) in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
#9 Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>::readField(Foam::Istream&) in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
#10 Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>::GeometricField(Foam::IOobject const&, Foam::fvMesh const&) in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
#11
in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
#12 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#13
in "/opt/openfoam211/platforms/linux64GccDPOpt/bin/pisoFoam"
Floating point exception (core dumped)

chegdan March 3, 2013 17:43

Zako,

"Floating point exception" is code for divide by zero or some other undefined numerical error. If you have something like a z0 = 0 and Href = 0 then there is going to be a log(0) in there for that BC. I tend to use 1e-20 instead of zero for small numbers that may induce this kind of error. Have a look at the BC itself in

Code:

$FOAM_SRC/turbulenceModels/incompressible/RAS/derivedFvPatchFields/atmBoundaryLayerInletVelocity
to track down exactly where this error is. Without seeing how you have defined the BC...I can't give you more info than this. Good Luck.

bigzakk March 4, 2013 07:40

Thanks a million its works :)

AbdelkaderDZ March 9, 2013 07:40

Problem with atmBoundaryLayerInletVelocity
 
Hi anyone,
I have error at the forth iteration when using atmBoundaryLayerInletVelocity for a simple case I use simpleFoam solver. Anyone can help me

ime = 4

DILUPBiCG: Solving for Ux, Initial residual = 0.0747753, Final residual = 0.00352462, No Iterations 1
DILUPBiCG: Solving for Uy, Initial residual = 0.0842028, Final residual = 0.00496445, No Iterations 1
DICPCG: Solving for p, Initial residual = 0.00994555, Final residual = 9.80074e-05, No Iterations 225
time step continuity errors : sum local = 0.0137186, global = 0.000340224, cumulative = -0.000110142
#0 Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam211/platforms/linuxGccDPOpt/lib/libOpenFOAM.so"
#1 Foam::sigFpe::sigHandler(int) in "/opt/openfoam211/platforms/linuxGccDPOpt/lib/libOpenFOAM.so"

Lieven March 9, 2013 14:46

Welcome to the forum AbdelkaderDZ.

For the looks of it, there is something wrong with your continuity. The cumulative error is simply way too big. If you are using a standard solver, this is often caused by incompatible boundary conditions. Could you post an overview of them of all fields (pressure, velocity, ...)?

Cheers,

L

AbdelkaderDZ March 10, 2013 03:10

Re:Re:Problem with atmBoundaryLayerInletVelocity
 
Thank you Lieven
I have used the standard simplefoam with the following boundary condition for u and p:
u boundary condition:

boundaryField
{
#include "include/ABLConditions"

outlet
{
type zeroGradient;
}

inlet
{
type atmBoundaryLayerInletVelocity;
Uref $Uref;
Href $Href;
n $windDirection;
z $zDirection;
z0 $z0;
value $internalField;
zGround $zGround;
}
upperWall
{
type symmetryPlane;
}
lowerWall
{
type fixedValue;
value uniform (0 0 0);
}
frontAndBack
{
type empty;
}
p boundary condition
boundaryField
{
inlet
{
type zeroGradient;
}

outlet
{
type fixedValue;
value uniform 0;
}

upperWall
{
type symmetryPlane;
}

lowerWall
{
type zeroGradient;
}

frontAndBack
{
type empty;
}
}

Lieven March 10, 2013 05:31

Nothing seems spectacular wrong with this so here are a few things you can do/check:
Does 'checkMesh' return 'mesh ok' (maybe post the final summary)?
Do you get the same problem when running with smaller time step?
One thing you can do is run your application using pimpleFoam instead of simpleFoam, which runs often more stable for larger time steps. Can you post the output of this here?
Which turbulence model are you using?

Chees,

L


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