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October 29, 2007, 12:29 |
Hi Holger ..
I am a new use
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#21 |
Senior Member
Nishant
Join Date: Mar 2009
Location: Glasgow, UK
Posts: 166
Rep Power: 17 |
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
__________________
Thanks and regards, Nishant |
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October 31, 2007, 11:23 |
My problem is now fixed..!! ht
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#22 |
Senior Member
Nishant
Join Date: Mar 2009
Location: Glasgow, UK
Posts: 166
Rep Power: 17 |
My problem is now fixed..!! []
__________________
Thanks and regards, Nishant |
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February 7, 2008, 20:35 |
Dear Foamers,
when I use my g
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#23 |
Member
Danielle PRL
Join Date: Mar 2009
Posts: 42
Rep Power: 17 |
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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July 23, 2008, 07:22 |
hi to all group,
i have one
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#24 |
New Member
Edwin Gonzalez
Join Date: Mar 2009
Posts: 4
Rep Power: 17 |
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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November 25, 2008, 02:48 |
I have the same problem with a
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#25 |
Guest
Posts: n/a
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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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November 25, 2008, 03:48 |
hi
I am using last version
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#26 |
Guest
Posts: n/a
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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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November 25, 2008, 03:51 |
The AMG solver does not exist,
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#27 |
Member
Pattyn Eric
Join Date: Mar 2009
Posts: 61
Rep Power: 17 |
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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November 25, 2008, 04:04 |
hi
I did add G but it is no
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#28 |
Guest
Posts: n/a
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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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November 25, 2008, 04:05 |
where I must add "agglomerator
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#29 |
Guest
Posts: n/a
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where I must add "agglomerator"
any suggestion thanks Emo |
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April 10, 2017, 02:18 |
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#30 | |
Member
Viraj Belekar
Join Date: Jun 2016
Posts: 68
Rep Power: 9 |
Quote:
I am getting a similar error. I am trying to simulate a steady state laminar flow in 5mm diameter cylindrical pipe. I have attached my log file, p, U, fvSchemes and fvSolution files. Please help. Regards Viraj |
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February 24, 2018, 01:22 |
timestep calculation
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#31 |
Member
Join Date: Oct 2017
Posts: 52
Rep Power: 8 |
can anyone tell me hot to access current and old timesteps ?
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February 24, 2018, 01:23 |
timestep
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#32 |
Member
Join Date: Oct 2017
Posts: 52
Rep Power: 8 |
can anyone tell me hot to access current and old timesteps ?
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February 26, 2018, 10:41 |
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#33 |
Member
Viraj Belekar
Join Date: Jun 2016
Posts: 68
Rep Power: 9 |
Hi,
OpenFOAM creates folders to write data for current and previous timesteps. You can access your data in the particular folder. Also you can use the following command to make a log file for your simulations: command | tee log |
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March 5, 2019, 06:06 |
how did you solve your problem
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#34 |
New Member
SHUBHAM ONAVE
Join Date: Mar 2019
Posts: 1
Rep Power: 0 |
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May 1, 2019, 21:56 |
Same problem with SIMPLE
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#35 |
New Member
sam zou
Join Date: May 2019
Posts: 2
Rep Power: 0 |
Dear all,
I am new to openfoam and I am trying to solve an asymmetric jet flow in free stream and my results are not satisfying. smoothSolver: Solving for Ux, Initial residual = 0.000508293, Final residual = 3.21941e-06, No Iterations 4 smoothSolver: Solving for Uy, Initial residual = 0.000940431, Final residual = 4.81773e-06, No Iterations 4 smoothSolver: Solving for Uz, Initial residual = 0.0107984, Final residual = 7.2382e-05, No Iterations 3 GAMG: Solving for p, Initial residual = 0.00121237, Final residual = 7.15837e-05, No Iterations 2 time step continuity errors : sum local = 5.58531e-05, global = 1.58563e-05, cumulative = 0.0521039 smoothSolver: Solving for epsilon, Initial residual = 0.000275732, Final residual = 1.74389e-06, No Iterations 4 smoothSolver: Solving for k, Initial residual = 0.000345624, Final residual = 2.17518e-06, No Iterations 4 The following is my fvscheme and fvsolution ddtSchemes { default steadyState; } gradSchemes { default Gauss linear; } divSchemes { default none; div(phi,U) bounded Gauss upwind limited; div(phi,k) bounded Gauss upwind; div(phi,epsilon) bounded Gauss upwind; div(phi,R) bounded Gauss upwind; div(R) Gauss linear; div(phi,nuTilda) bounded Gauss upwind; div((nuEff*dev2(T(grad(U))))) Gauss linear; } laplacianSchemes { default Gauss linear limited 1; } interpolationSchemes { default linear; } snGradSchemes { default corrected; } fluxRequired { default no; p ; } solvers { p { solver GAMG; tolerance 1e-07; relTol 0.1; smoother GaussSeidel; nPreSweeps 0; nPostSweeps 2; cacheAgglomeration on; agglomerator faceAreaPair; nCellsInCoarsestLevel 10; mergeLevels 1; } "(U|k|epsilon|R|nuTilda)" { solver smoothSolver; smoother symGaussSeidel; tolerance 1e-07; relTol 0.01; } } SIMPLE { nNonOrthogonalCorrectors 0; residualControl { p 1e-4; Ux 1e-4; Uy 1e-4; //U "(k|epsilon)" 1e-4; } } relaxationFactors { fields { p 0.3; } equations { U 0.7; k 0.7; epsilon 0.7; R 0.7; nuTilda 0.7; } } Please help! Thank you!!! |
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August 22, 2019, 17:56 |
Very large continuity error
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#36 | |
Member
Chris Harding
Join Date: Dec 2016
Posts: 76
Rep Power: 9 |
Quote:
I have checked my boundary conditions. Velocity: inlet: fixedValue, uniorm (0 0 25); outlet: zeroGradient; all walls: fixedValue uniform (0 0 0); Pressure: inlet: zeroGradient; outlet: uniform 0; all walls: zeroGradient; My continuity errors: were x.xe+35 or more. I tightened the relTol of pressure to 1e-06 in hopes that the errors would get under control. The flow is very turbulent. Any suggestions on how to get continuity errors under control? |
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August 22, 2019, 19:18 |
Is time step a valid way to drop continuity errors
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#37 | |
Member
Chris Harding
Join Date: Dec 2016
Posts: 76
Rep Power: 9 |
Quote:
Please forgive me for the ignorant question. I am new, don't know the code, and I am trying to learn about how to increase accuracy. I changed the timeStep and my continuity dropped to the range of x.xe-07 and -x.xe-07. I also changed my fvSchemes though. Still, the continuity errors dropped, during the previous run, when I changed the timeStep in the controlDict. Last edited by HappyS5; August 22, 2019 at 19:25. Reason: Add information |
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June 22, 2020, 11:16 |
Continuity Error
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#38 |
Member
Himanshu
Join Date: Jan 2017
Posts: 34
Rep Power: 9 |
Hello ,
Can anyone explain what is the difference between sum local ,global and cumulative in continuity error. Eg.: "time step continuity errors : sum local = 0.043, global = 1.13e-007, cumulative = 1.33e-007" and Which one we have to check for deciding convergence? P.S.: I am coming from Fluent background where we only see one value of continuity residue. Thanks |
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