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Old   October 29, 2007, 13:29
Default Hi Holger .. I am a new use
  #21
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Nishant
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Hi Holger ..
I am a new user to Openfoam. i am also working on a cylindrical pipe flow geometry with water as fluid in icoFoam and simplefoam module. The problem consist of a circular face as a inlet and another face as a outlet. (see p and U file at the end)
My pre-compiled OpenFoam was working fine for the tutorial problems but now with my current cylinderical pipe problem, this is give some error:
error is:

#0 Foam::error::printStack(Foam: :-Ostream&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/home/343880/OpenFOAM/OpenFOAM- 1.4.1/lib/linuxGccDPOpt/libOpenFOAM.so"
#2 Uninterpreted: [0x110420]
#3 void Foam::fvc::surfaceIntegrate<foam::vector<double> >(Foam::Field<foam::vector<double> >&, Foam::GeometricField<foam::vector<double>, Foam::fvsPatchField, Foam::surfaceMesh> const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libfiniteVolume.so"
#4 Foam::tmp<foam::geometricfield<foam::vector<double >, Foam::fvPatchField, Foam::volMesh> > Foam::fvc::surfaceIntegrate<foam::vector<double> >(Foam::GeometricField<foam::vector<double>, Foam::fvsPatchField, Foam::surfaceMesh> const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libfiniteVolume.so"
#5 Foam::tmp<foam::geometricfield<foam::vector<double >, Foam::fvPatchField, Foam::volMesh> > Foam::fvc::surfaceIntegrate<foam::vector<double> >(Foam::tmp<foam::geometricfield<foam::vector<doub le>, Foam::fvsPatchField, Foam::surfaceMesh> > const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libfiniteVolume.so"
#6 Foam::fv::gaussDivScheme<foam::tensor<double> >::fvcDiv(Foam::GeometricField<foam::tensor<double >, Foam::fvPatchField, Foam::volMesh> const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libfiniteVolume.so"
#7 Foam::tmp<foam::geometricfield<foam::innerproduct< foam::vector<double>, Foam::Tensor<double> >::type, Foam::fvPatchField, Foam::volMesh> > Foam::fvc::div<foam::tensor<double> >(Foam::GeometricField<foam::tensor<double>, Foam::fvPatchField, Foam::volMesh> const&, Foam::word const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libincompressibleTurbule nceModels.so"
#8 Foam::tmp<foam::geometricfield<foam::innerproduct< foam::vector<double>, Foam::Tensor<double> >::type, Foam::fvPatchField, Foam::volMesh> > Foam::fvc::div<foam::tensor<double> >(Foam::GeometricField<foam::tensor<double>, Foam::fvPatchField, Foam::volMesh> const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libincompressibleTurbule nceModels.so"
#9 Foam::tmp<foam::geometricfield<foam::innerproduct< foam::vector<double>, Foam::Tensor<double> >::type, Foam::fvPatchField, Foam::volMesh> > Foam::fvc::div<foam::tensor<double> >(Foam::tmp<foam::geometricfield<foam::tensor<doub le>, Foam::fvPatchField, Foam::volMesh> > const&) in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libincompressibleTurbule nceModels.so"
#10 Foam::turbulenceModels::kEpsilon::divR(Foam::Geome tricField<foam::vector<double> , Foam::fvPatchField, Foam::volMesh>&) const in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/lib/linuxGccDPOpt/libincompressibleTurbule nceModels.so"
#11 main in "/home/343880/OpenFOAM/OpenFOAM-1.4.1/applications/bin/linuxGccDPOpt/simpleFoam"
#12 __libc_start_main in "/lib/libc.so.6"
#13 Foam::regIOobject::readIfModified() in "/home/343880/OpenFOAM/OpenFOAM- 1.4.1/applications/bin/linuxGccDPOpt/simpleFoam"
Floating point exception





The files, i am using are listed below:

1. transportproperties:

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

transportModel Newtonian;

nu nu [0 2 -1 0 0 0 0] 0.89;

CrossPowerLawCoeffs
{
nu0 nu0 [0 2 -1 0 0 0 0] 0.89;
nuInf nuInf [0 2 -1 0 0 0 0] 0.89;
m m [0 0 1 0 0 0 0] 1;
n n [0 0 0 0 0 0 0] 1;
}

BirdCarreauCoeffs
{
nu0 nu0 [0 2 -1 0 0 0 0] 0.89;
nuInf nuInf [0 2 -1 0 0 0 0] 0.89;
k k [0 0 1 0 0 0 0] 0;
n n [0 0 0 0 0 0 0] 1;
}


2. blockMeshDict

arguments "/home/343880/OpenFOAM/343880-1.4.1/run/tutorials/icoFoam/pipeflow" off;

convertToMeters 0.01;

vertices
(
(0.3 0 0)
(0 0.3 0)
(-0.3 0 0)
(0 -0.3 0)
(1 0 0)
(0 1 0)
(-1 0 0)
(0 -1 0)
(0.3 0 10)
(0 0.3 10)
(-0.3 0 10)
(0 -0.3 10)
(1 0 10)
(0 1 10)
(-1 0 10)
(0 -1 10)
);

blocks
(
hex (0 1 2 3 8 9 10 11) (10 10 20) simpleGrading (1 1 1)
hex (0 1 5 4 8 9 13 12) (10 10 20) simpleGrading (1 1 1)
hex (1 2 6 5 9 10 14 13) (10 10 20) simpleGrading (1 1 1)
hex (2 3 7 6 10 11 15 14) (10 10 20) simpleGrading (1 1 1)
hex (3 0 4 7 11 8 12 15) (10 10 20) simpleGrading (1 1 1)


);

edges
(
arc 4 5 (0.866 0.5 0)
arc 5 6 (-0.866 0.5 0)
arc 6 7 (-0.866 -0.5 0)
arc 7 4 (0.866 -0.5 0)
arc 12 13 (0.866 0.5 40)
arc 13 14 (-0.866 0.5 40)
arc 14 15 (-0.866 -0.5 40)
arc 15 12 (0.866 -0.5 40)
);

patches
(
wall fixedWalls
(
(4 5 13 12)
(5 6 14 13)
(6 7 15 14)
(7 4 12 15)
)
patch inlet
(
(0 3 2 1)
(0 4 7 3)
(0 1 5 4)
(1 2 6 5)
(2 3 7 6)
)

patch outlet
(
(8 9 10 11)
(8 11 15 12)
(9 8 12 13)
(10 9 13 14)
(10 14 15 11)

)
);

mergePatchPairs
(
);


// ************************************************** *********************** //

3. p file



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

internalField uniform 0;

boundaryField
{
inlet
{
type zeroGradient;
}

outlet
{
type fixedValue;
value uniform 0;
}

fixedWalls
{
type zeroGradient;
}

}


// ************************************************** *********************** //

4. U file



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

internalField uniform (0 0 0);

boundaryField
{
inlet
{
type fixedValue;
value uniform (0 0 10.005);
}

outlet
{
type zeroGradient;
}

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

}


// ************************************************** *********************** //




I saw your blogs on discussion group and i was glad to know that you could be able to run the same problem succesfully. I hope you could be able to guide me in this regard.
I look forward to hearing from you soon.



Nishant
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Thanks and regards,

Nishant
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Old   October 31, 2007, 12:23
Default My problem is now fixed..!! ht
  #22
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Nishant
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My problem is now fixed..!! []
__________________
Thanks and regards,

Nishant
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Old   February 7, 2008, 21:35
Default Dear Foamers, when I use my g
  #23
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Danielle PRL
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Dear Foamers,
when I use my geometry in Fluent 6.3 with one or two phases I have a realistic result. In O.Foam 1.4.1 neither with turbFoam nor with twoPhaseEulerFoam gives a good (realsitic) result. when I check my mesh, I get the following message:

Time = constant

Mesh stats
points: 314704
edges: 1088715
faces: 1277556
internal faces: 1211202
cells: 492171
boundary patches: 13
point zones: 0
face zones: 0
cell zones: 2

Number of cells of each type:
hexahedra: 257595
prisms: 0
wedges: 0
pyramids: 4884
tet wedges: 0
tetrahedra: 229692
polyhedra: 0

Checking topology...
Boundary definition OK.
Point usage OK.
Upper triangular ordering OK.
Topological cell zip-up check OK.
Face vertices OK.
Number of identical duplicate faces (baffle faces): 11380
Face-face connectivity OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces ...
Patch Faces Points Surface
wall_cylin_int_Pied 22752 10349 multiply connected surface (shared edge)
wall_cylin_ext_G 8448 8624 ok (not multiply connected)
wall_capt_inlet_G 960 980 ok (not multiply connected)
inlet3 142 76 ok (not multiply connected)
inlet2 140 75 ok (not multiply connected)
outlet 25 33 ok (not multiply connected)
Wall_top 2653 2755 ok (not multiply connected)
inlet1 78 43 ok (not multiply connected)
wall_buttom 2669 1406 ok (not multiply connected)
wal_capt_inlet_F 873 685 ok (not multiply connected)
wall_cylin_inter 809 420 multiply connected surface (shared edge)
wall_cylin_ext_F 24925 19277 ok (not multiply connected)
wall_disc_inlet 1880 949 ok (not multiply connected)
<<Writing 10349 conflicting points to set nonManifoldPoints

Checking geometry...
Domain bounding box: (-0.139998 -0.139998 -8.61533e-16) (0.139998 0.139997 0.99)
Boundary openness (-1.08376e-17 2.8904e-17 -1.39722e-16) OK.
Max cell openness = 1.66038e-15 OK.
Max aspect ratio = 21.4331 OK.
Minumum face area = 1.22452e-07. Maximum face area = 8.99153e-05. Face area magnitudes OK.
Min volume = 2.74672e-11. Max volume = 2.55601e-07. Total volume = 0.0347228. Cell volumes OK.
Mesh non-orthogonality Max: 84.9996 average: 12.6589
*Number of severely non-orthogonal faces: 49.
Non-orthogonality check OK.
<<Writing 49 non-orthogonal faces to set nonOrthoFaces
Face pyramids OK.
Max skewness = 1.33507 OK.
Min/max edge length = 0.000218421 0.0171268 OK.
All angles in faces OK.
Face flatness (1 = flat, 0 = butterfly) : average = 1 min = 0.995346
All face flatness OK.

Mesh OK.

End


1. which value should I give to nNonOrthogonalCorrectors in fvSolution ?

2. Is my mesh the problem ?(when I use 1.4 version alot of error appear in checkMesh).

thank you for help
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Old   July 23, 2008, 07:22
Default hi to all group, i have one
  #24
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Edwin Gonzalez
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hi to all group,

i have one question:

what so important are the time step continuity errors in a steady state simulation?

what happen if they are big?

edwin
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Old   November 25, 2008, 03:48
Default I have the same problem with a
  #25
emilianyassenov
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I have the same problem with anja I have done the steps above and I have following error

Time = 0.0001

Courant Number mean: 0 max: 9.2665e-08
DILUPBiCG: Solving for Ux, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for Uy, Initial residual = 1, Final residual = 4.2086e-16, No Iterations 1
DILUPBiCG: Solving for Uz, Initial residual = 0, Final residual = 0, No Iterations 0


Unknown symmetric matrix solver AMG

Valid symmetric matrix solvers are :

4
(
ICCG
smoothSolver
PCG
GAMG
)


file: /home/rkahraman/OpenFOAM/rkahraman-1.5/run/tutorials/project/shape/system/fvSolu tion::p at line 20.

From function lduMatrix::solver::New
in file matrices/lduMatrix/lduMatrix/lduMatrixSolver.C at line 78.

FOAM exiting

someone can help me?

Emo
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Old   November 25, 2008, 04:48
Default hi I am using last version
  #26
emilianyassenov
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hi

I am using last version of OpenFOAM and also IcoFoam but that instructions above not working in my case I have a problem with AMG solver...

Emo
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Old   November 25, 2008, 04:51
Default The AMG solver does not exist,
  #27
ep4
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Pattyn Eric
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The AMG solver does not exist, the error message says that you can to use the GAMG solver to solve symmetric matrix.
Just add the G befor AMG in the system/fvSolution file.
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Old   November 25, 2008, 05:04
Default hi I did add G but it is no
  #28
emilianyassenov
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hi

I did add G but it is not working as well

then I had that

keyword agglomerator is undefined in dictionary "/home/rkahraman/OpenFOAM/rkahraman-1.5/run/tutorials/project/shape/system/fvSol ution::p"

file: /home/rkahraman/OpenFOAM/rkahraman-1.5/run/tutorials/project/shape/system/fvSolu tion::p

From function dictionary::lookupEntry(const word& keyword) const
in file db/dictionary/dictionary.C at line 213.

Emo
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Old   November 25, 2008, 05:05
Default where I must add "agglomerator
  #29
emilianyassenov
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where I must add "agglomerator"

any suggestion

thanks Emo
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