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-   -   After 3 iterations the case is kill by system (https://www.cfd-online.com/Forums/openfoam/108028-after-3-iterations-case-kill-system.html)

Bombolati October 12, 2012 11:23

After 3 iterations the case is kill by system
 
Hi at all!
I'm doing a simulation in a combustion chamber with reactingFoam as solutor. The mesh dimension is about 9000000 cells so I have to run my case in parallel. I've decompose the case with the utility decomposePar and I've submitted my job. The job runs, but after the third iteration OF kills my case. The system gives me two files, one is the output (in which it writes the iterations) and the other is the error file (in which it writes the error messages). I post here only the first one because the error file is not understandable:

Create time

Create mesh for time = 0


Reading g
Creating combustion model

Selecting combustion model PaSR<psiChemistryCombustionModel>
Selecting psiChemistryModel ODEChemistryModel<gasThermoPhysics>
Selecting thermodynamics package hsPsiMixtureThermo<reactingMixture<gasThermoPhysic s>>
Selecting chemistryReader foamChemistryReader
ODEChemistryModel: Number of species = 5 and reactions = 1
Selecting ODE solver SIBS
Reading field U

Reading/calculating face flux field phi

Creating turbulence model.

Selecting turbulence model type RASModel
Selecting RAS turbulence model kEpsilon
kEpsilonCoeffs
{
Cmu 0.09;
C1 1.44;
C2 1.92;
C3 -0.33;
sigmak 1;
sigmaEps 1.3;
Prt 1;
}

Creating field dpdt

Creating field kinetic energy K

Courant Number mean: 8.47313e-08 max: 0.00822867

PIMPLE: Operating solver in PISO mode


Starting time loop

Courant Number mean: 8.38923e-08 max: 0.0081472
deltaT = 1.17647e-07
Time = 1.17647e-07

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for O2, Initial residual = 0.403158, Final residual = 0.604033, No Iterations 1001
DILUPBiCG: Solving for H2O, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for CH4, Initial residual = 1, Final residual = 2.77956e-09, No Iterations 2
DILUPBiCG: Solving for CO2, Initial residual = 0, Final residual = 0, No Iterations 0

DILUPBiCG: Solving for hs, Initial residual = 1, Final residual = 2.62501e-08, No Iterations 2
T gas min/max = 289.99, 290.075
DICPCG: Solving for p, Initial residual = 1, Final residual = 0.0398273, No Iterations 2
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 4.1802e-08, global = 1.28528e-08, cumulative = 1.28528e-08
DICPCG: Solving for p, Initial residual = 0.000255185, Final residual = 5.58144e-07, No Iterations 5
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 2.10976e-10, global = 3.33482e-11, cumulative = 1.28861e-08
DILUPBiCG: Solving for epsilon, Initial residual = 1, Final residual = 0.0544124, No Iterations 1001
bounding epsilon, min: -137998 max: 201701 average: 36.6196
DILUPBiCG: Solving for k, Initial residual = 1, Final residual = 9.37466e-07, No Iterations 14
bounding k, min: -0.00225299 max: 1 average: 0.0018574
ExecutionTime = 442.31 s ClockTime = 445 s

Courant Number mean: 1.62656e-06 max: 0.274072
deltaT = 8.51927e-08
Time = 2.0284e-07

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for O2, Initial residual = 0.999989, Final residual = 0.0161316, No Iterations 1001
DILUPBiCG: Solving for H2O, Initial residual = 0.914623, Final residual = 0.0295428, No Iterations 1001
DILUPBiCG: Solving for CH4, Initial residual = 1, Final residual = 3.56746e-07, No Iterations 13
DILUPBiCG: Solving for CO2, Initial residual = 0.929003, Final residual = 0.605438, No Iterations 1001
DILUPBiCG: Solving for hs, Initial residual = 1, Final residual = 3.58028e-07, No Iterations 13
T gas min/max = 289.724, 295.613
DICPCG: Solving for p, Initial residual = 0.00303426, Final residual = 0.000263235, No Iterations 1
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 1.00107e-07, global = 5.77487e-08, cumulative = 7.06349e-08
DICPCG: Solving for p, Initial residual = 0.000283424, Final residual = 2.9303e-07, No Iterations 4
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 3.11907e-10, global = -9.62024e-12, cumulative = 7.06252e-08
DILUPBiCG: Solving for epsilon, Initial residual = 1, Final residual = 1.76135e-07, No Iterations 13
DILUPBiCG: Solving for k, Initial residual = 1, Final residual = 1219.46, No Iterations 1001
bounding k, min: -1.21469e+13 max: 4.22607e+14 average: 9.00783e+08
ExecutionTime = 1074.09 s ClockTime = 1078 s

Courant Number mean: 1.69728e-06 max: 0.411373
deltaT = 4.13382e-08
Time = 2.44178e-07

diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for O2, Initial residual = 0.999999, Final residual = 1.94716e-06, No Iterations 1001
DILUPBiCG: Solving for H2O, Initial residual = 1, Final residual = 8.35736e-07, No Iterations 44
DILUPBiCG: Solving for CH4, Initial residual = 1, Final residual = 9.30056e-07, No Iterations 45
DILUPBiCG: Solving for CO2, Initial residual = 1, Final residual = 6.7396e-07, No Iterations 44
DILUPBiCG: Solving for hs, Initial residual = 1, Final residual = 9.9648e-07, No Iterations 46
T gas min/max = 289.606, 300.728
DICPCG: Solving for p, Initial residual = 0.0133159, Final residual = 9.70516e-06, No Iterations 1
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 7.10937e-09, global = 1.8755e-09, cumulative = 7.25007e-08
DICPCG: Solving for p, Initial residual = 0.000272168, Final residual = 6.89739e-07, No Iterations 2
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 1.068e-09, global = -3.76896e-10, cumulative = 7.21238e-08
DILUPBiCG: Solving for epsilon, Initial residual = 1, Final residual = 7.16581e-07, No Iterations 140
bounding epsilon, min: -1608.29 max: 2506.99 average: 33.376
255 additional processes aborted (not shown)


PS:

Read file <react.err> for stderr output of this job.

Someone knows why OF kills the job? thank you very much for the hints!

wyldckat October 13, 2012 03:53

Greetings Bombolati,

Uhm... Have you looked at the numbers?
Quote:

Originally Posted by Bombolati (Post 386302)
...
DILUPBiCG: Solving for O2, Initial residual = 0.403158, Final residual = 0.604033, No Iterations 1001
...
DILUPBiCG: Solving for epsilon, Initial residual = 1, Final residual = 0.0544124, No Iterations 1001
bounding epsilon, min: -137998 max: 201701 average: 36.6196
...
DILUPBiCG: Solving for O2, Initial residual = 0.999989, Final residual = 0.0161316, No Iterations 1001
DILUPBiCG: Solving for H2O, Initial residual = 0.914623, Final residual = 0.0295428, No Iterations 1001
DILUPBiCG: Solving for CH4, Initial residual = 1, Final residual = 3.56746e-07, No Iterations 13
DILUPBiCG: Solving for CO2, Initial residual = 0.929003, Final residual = 0.605438, No Iterations 1001
...
DILUPBiCG: Solving for k, Initial residual = 1, Final residual = 1219.46, No Iterations 1001
bounding k, min: -1.21469e+13 max: 4.22607e+14 average: 9.00783e+08
...
DILUPBiCG: Solving for O2, Initial residual = 0.999999, Final residual = 1.94716e-06, No Iterations 1001
...
DILUPBiCG: Solving for epsilon, Initial residual = 1, Final residual = 7.16581e-07, No Iterations 140
bounding epsilon, min: -1608.29 max: 2506.99 average: 33.376
255 additional processes aborted (not shown)

Those numbers are a symptom of the reason why OpenFOAM stopped working! It didn't kill voluntarily or because it felt like it, it actually crashed due to a division by zero or by infinite or something similar! ;)

As for the reason for the crash... plenty of possibilities, of which these are some of the many reasons why this might have happened:
  • Bad boundary conditions.
  • Bad mesh.


From your description, I would guess that you didn't prepare properly for scaling things up to the 256 sub-domains. You should have started with a small example case that reflected your setup, because that way you would have found out about this problem sooner, because divisions by zero or infinite are very common for people that have just started using OpenFOAM ;)

Best regards,
Bruno

Tobi October 16, 2012 08:26

A other solution would be to use the flamelet-model!

Nice to use - simple and smart.

Tobi

Bombolati October 17, 2012 04:58

I've tried to change the initial conditions but it occurs the same error. To check mesh I run the checkMesh utility ad I find a strange situation:
if I run this utility from a pc that has OF v.2.1.1 it gives me ok;
if I run the same utility on the v.2.1.0 it gives me an error on the last check:


Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 1527113
faces: 17663239
internal faces: 17406505
cells: 8766526
boundary patches: 20
point zones: 0
face zones: 4
cell zones: 1

Overall number of cells of each type:
hexahedra: 0
prisms: 0
wedges: 0
pyramids: 3640
tet wedges: 0
tetrahedra: 8762886
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces ...
Patch Faces Points Surface topology
CameraFSup 40844 20654 ok (non-closed singly connected)
IngAria 12544 6427 ok (non-closed singly connected)
CombIng2 1684 891 ok (non-closed singly connected)
CombIng1 1682 890 ok (non-closed singly connected)
CameraFL 10446 5408 ok (non-closed singly connected)
MixerFint 7254 3817 ok (non-closed singly connected)
MixerFext 11222 5788 ok (non-closed singly connected)
IniettoreAriaFint 12196 6261 ok (non-closed singly connected)
TestaPiano 1959 1040 ok (non-closed singly connected)
IniettoreAriaFext 36654 18584 ok (non-closed singly connected)
Bordo 12707 6474 ok (non-closed singly connected)
CameraFinf 16196 8269 ok (non-closed singly connected)
CameraFL2_sh 9308 4792 ok (non-closed singly connected)
CamerFL2 9308 4792 ok (non-closed singly connected)
CameraFL1_sh 19082 9725 ok (non-closed singly connected)
CamerFL1 19082 9725 ok (non-closed singly connected)
MixerFL_sh 1820 1908 ok (non-closed singly connected)
MixFL 1820 1908 ok (non-closed singly connected)
IniettoreAriaFL_sh 15463 7907 ok (non-closed singly connected)
IniettorAriaFL 15463 7907 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-3.2684804e-19 -2.1706595e-17 -7.1054274e-18) (0.098 0.098 0.057)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Boundary openness (1.5454146e-17 -3.0346545e-15 8.5450276e-17) OK.
Max cell openness = 3.1859414e-16 OK.
Max aspect ratio = 8.8739399 OK.
Minumum face area = 2.1118586e-09. Maximum face area = 1.3930115e-06. Face area magnitudes OK.
Min volume = 5.4359761e-14. Max volume = 4.4160393e-10. Total volume = 0.00023160389. Cell volumes OK.
Mesh non-orthogonality Max: 67.249804 average: 19.728405
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.95427342 OK.
**Error in coupled point location: 45583 faces have their 0th vertex not opposite their coupled equivalent. Average mismatch 0.038782438.
<<Writing 45583 faces with incorrectly matched 0th vertex to set coupledFaces

Failed 1 mesh checks.

End


unfortunately, the version on the parallel platform is the 2.1.0. What could I do?
Thank you

wyldckat October 20, 2012 16:30

Greetings Francesco,

Mmm... this is indeed strange. Try doing the complete check on both versions:
Code:

checkMesh -allTopology -allGeometry
There are a few possibilities I can think of:
  • One would be to redo the mesh, to get one with a better mesh quality.
  • Another would be to try using polyDualMesh, which will convert your tetrahedral mesh into a polyhedral, thus making it more efficient and should have a bit better quality.
    But it isn't a silver bullet! If the mesh has an accentuated imperfection, polyDualMesh will not be able to do its magic.
    For more on this utility, I've written some pointers about it here: http://www.cfd-online.com/Forums/ope...tml#post378734 post #14
  • Yet another would be to restructure/redo your case into something more simple and then work from that point forward. For example, reduce the complexity of the case to a few cubes/rectangles... in an extreme case, you might even want to stick to a single cube with strategically placed inlets and outlets, for representing what you're trying to solve. When you've got that working, gradually increase the complexity of the geometry.
    Always remember that this is OpenFOAM you're dealing with! Until you are not fully familiar with it, do not go straight for the solution at the first try! Only if and when you are familiar enough with a particular type of case setup, will you be able to setup those cases at the first or second attempt ;)
Best regards and good luck!
Bruno

Bombolati October 23, 2012 03:53

Ok, I've done the checkMesh that you hint me and for the 2.1.0 version this is the result:

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 1527113
faces: 17663239
internal faces: 17406505
cells: 8766526
boundary patches: 20
point zones: 0
face zones: 4
cell zones: 1

Overall number of cells of each type:
hexahedra: 0
prisms: 0
wedges: 0
pyramids: 3640
tet wedges: 0
tetrahedra: 8762886
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Topological cell zip-up check OK.
Face-face connectivity OK.
<<Writing 576 cells with with two non-boundary faces to set twoInternalFacesCells
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces ...
Patch Faces Points Surface topology Bounding box
CameraFSup 40844 20654 ok (non-closed singly connected) (1.83691e-18 -1.98697e-17 0.057) (0.098 0.098 0.057)
IngAria 12544 6427 ok (non-closed singly connected) (1.40097e-18 -5.63649e-18 -7.10543e-18) (0.018 0.018 -7.10543e-18)
CombIng2 1684 891 ok (non-closed singly connected) (0.00621508 0.00142632 0.025) (0.00736313 0.00419796 0.028)
CombIng1 1682 890 ok (non-closed singly connected) (0.00142632 0.00621508 0.025) (0.00419796 0.00736313 0.028)
CameraFL 10446 5408 ok (non-closed singly connected) (1.54106e-17 -1.42109e-17 0.027) (0.098 0.098 0.057)
MixerFint 7254 3817 ok (non-closed singly connected) (2.90746e-19 -1.87531e-18 0.023) (0.0075 0.0075 0.03)
MixerFext 11222 5788 ok (non-closed singly connected) (1.23214e-18 -4.4964e-18 0.023) (0.018 0.018 0.03)
IniettoreAriaFint 12196 6261 ok (non-closed singly connected) (2.90746e-19 -2.26208e-18 -7.10543e-18) (0.006 0.006 0.023)
TestaPiano 1959 1040 ok (non-closed singly connected) (1.83691e-19 -1.46982e-18 0.03) (0.0075 0.0075 0.03)
IniettoreAriaFext 36654 18584 ok (non-closed singly connected) (1.23214e-18 -4.4964e-18 -7.10543e-18) (0.018 0.018 0.023)
Bordo 12707 6474 ok (non-closed singly connected) (2.53981e-18 -4.39687e-18 0.027) (0.024 0.024 0.03)
CameraFinf 16196 8269 ok (non-closed singly connected) (3.12488e-18 -2.17066e-17 0.027) (0.098 0.098 0.027)
CameraFL2_sh 9308 4792 ok (non-closed singly connected) (0.024 -2.17066e-17 0.027) (0.098 -8.94476e-19 0.057)
CamerFL2 9308 4792 ok (non-closed singly connected) (1.19323e-18 0.024 0.027) (2.28941e-17 0.098 0.057)
CameraFL1_sh 19082 9725 ok (non-closed singly connected) (1.83691e-19 1.83691e-19 0.03) (7.14048e-18 0.024 0.057)
CamerFL1 19082 9725 ok (non-closed singly connected) (1.83691e-19 -6.04122e-18 0.03) (0.024 1.83691e-18 0.057)
MixerFL_sh 1820 1908 ok (non-closed singly connected) (0.0075 -4.4964e-18 0.023) (0.018 -4.01533e-19 0.03)
MixFL 1820 1908 ok (non-closed singly connected) (3.04229e-19 0.0075 0.023) (4.26287e-18 0.018 0.03)
IniettoreAriaFL_sh 15463 7907 ok (non-closed singly connected) (0.006 -5.63649e-18 -7.10543e-18) (0.018 -9.35895e-19 0.023)
IniettorAriaFL 15463 7907 ok (non-closed singly connected) (-3.26848e-19 0.006 -7.10543e-18) (3.08186e-18 0.018 0.023)

Checking geometry...
Overall domain bounding box (-3.26848e-19 -2.17066e-17 -7.10543e-18) (0.098 0.098 0.057)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Boundary openness (1.54541e-17 -3.03465e-15 8.54503e-17) OK.
Max cell openness = 3.18594e-16 OK.
Max aspect ratio = 8.87394 OK.
Minumum face area = 2.11186e-09. Maximum face area = 1.39301e-06. Face area magnitudes OK.
Min volume = 5.43598e-14. Max volume = 4.41604e-10. Total volume = 0.000231604. Cell volumes OK.
Mesh non-orthogonality Max: 67.2498 average: 19.7284
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.954273 OK.
**Error in coupled point location: 45583 faces have their 0th vertex not opposite their coupled equivalent. Average mismatch 0.0387824.
<<Writing 45583 faces with incorrectly matched 0th vertex to set coupledFaces
***Error in face tets: 91346 faces with low quality or negative volume decomposition tets.
<<Writing 91346 faces with low quality or negative volume decomposition tets to set lowQualityTetFaces
Min/max edge length = 5.29271e-05 0.00201282 OK.
All angles in faces OK.
Face flatness (1 = flat, 0 = butterfly) : average = 1 min = 1
All face flatness OK.
Cell determinant (wellposedness) : minimum: 0 average: 1.5153
***Cells with small determinant found, number of cells: 1888
<<Writing 1888 under-determined cells to set underdeterminedCells
Concave cell check OK.

Failed 3 mesh checks.

End

And for the 2.1.1 version:

Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 1527113
faces: 17663239
internal faces: 17406505
cells: 8766526
boundary patches: 20
point zones: 0
face zones: 4
cell zones: 1

Overall number of cells of each type:
hexahedra: 0
prisms: 0
wedges: 0
pyramids: 3640
tet wedges: 0
tetrahedra: 8762886
polyhedra: 0

Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Topological cell zip-up check OK.
Face-face connectivity OK.
<<Writing 576 cells with with two non-boundary faces to set twoInternalFacesCells
Number of regions: 1 (OK).

Checking patch topology for multiply connected surfaces ...
Patch Faces Points Surface topology Bounding box
CameraFSup 40844 20654 ok (non-closed singly connected) (1.83691e-18 -1.98697e-17 0.057) (0.098 0.098 0.057)
IngAria 12544 6427 ok (non-closed singly connected) (1.40097e-18 -5.63649e-18 -7.10543e-18) (0.018 0.018 -7.10543e-18)
CombIng2 1684 891 ok (non-closed singly connected) (0.00621508 0.00142632 0.025) (0.00736313 0.00419796 0.028)
CombIng1 1682 890 ok (non-closed singly connected) (0.00142632 0.00621508 0.025) (0.00419796 0.00736313 0.028)
CameraFL 10446 5408 ok (non-closed singly connected) (1.54106e-17 -1.42109e-17 0.027) (0.098 0.098 0.057)
MixerFint 7254 3817 ok (non-closed singly connected) (2.90746e-19 -1.87531e-18 0.023) (0.0075 0.0075 0.03)
MixerFext 11222 5788 ok (non-closed singly connected) (1.23214e-18 -4.4964e-18 0.023) (0.018 0.018 0.03)
IniettoreAriaFint 12196 6261 ok (non-closed singly connected) (2.90746e-19 -2.26208e-18 -7.10543e-18) (0.006 0.006 0.023)
TestaPiano 1959 1040 ok (non-closed singly connected) (1.83691e-19 -1.46982e-18 0.03) (0.0075 0.0075 0.03)
IniettoreAriaFext 36654 18584 ok (non-closed singly connected) (1.23214e-18 -4.4964e-18 -7.10543e-18) (0.018 0.018 0.023)
Bordo 12707 6474 ok (non-closed singly connected) (2.53981e-18 -4.39687e-18 0.027) (0.024 0.024 0.03)
CameraFinf 16196 8269 ok (non-closed singly connected) (3.12488e-18 -2.17066e-17 0.027) (0.098 0.098 0.027)
CameraFL2_sh 9308 4792 ok (non-closed singly connected) (0.024 -2.17066e-17 0.027) (0.098 -8.94476e-19 0.057)
CamerFL2 9308 4792 ok (non-closed singly connected) (1.19323e-18 0.024 0.027) (2.28941e-17 0.098 0.057)
CameraFL1_sh 19082 9725 ok (non-closed singly connected) (1.83691e-19 1.83691e-19 0.03) (7.14048e-18 0.024 0.057)
CamerFL1 19082 9725 ok (non-closed singly connected) (1.83691e-19 -6.04122e-18 0.03) (0.024 1.83691e-18 0.057)
MixerFL_sh 1820 1908 ok (non-closed singly connected) (0.0075 -4.4964e-18 0.023) (0.018 -4.01533e-19 0.03)
MixFL 1820 1908 ok (non-closed singly connected) (3.04229e-19 0.0075 0.023) (4.26287e-18 0.018 0.03)
IniettoreAriaFL_sh 15463 7907 ok (non-closed singly connected) (0.006 -5.63649e-18 -7.10543e-18) (0.018 -9.35895e-19 0.023)
IniettorAriaFL 15463 7907 ok (non-closed singly connected) (-3.26848e-19 0.006 -7.10543e-18) (3.08186e-18 0.018 0.023)

Checking geometry...
Overall domain bounding box (-3.26848e-19 -2.17066e-17 -7.10543e-18) (0.098 0.098 0.057)
Mesh (non-empty, non-wedge) directions (1 1 1)
Mesh (non-empty) directions (1 1 1)
Boundary openness (1.54541e-17 -3.03465e-15 8.54503e-17) OK.
Max cell openness = 3.18594e-16 OK.
Max aspect ratio = 8.87394 OK.
Minumum face area = 2.11186e-09. Maximum face area = 1.39301e-06. Face area magnitudes OK.
Min volume = 5.43598e-14. Max volume = 4.41604e-10. Total volume = 0.000231604. Cell volumes OK.
Mesh non-orthogonality Max: 67.2498 average: 19.7284
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.954273 OK.
Coupled point location match (average 3.46652e-20) OK.
Face tets OK.
Min/max edge length = 5.29271e-05 0.00201282 OK.
All angles in faces OK.
Face flatness (1 = flat, 0 = butterfly) : average = 1 min = 1
All face flatness OK.
Cell determinant (wellposedness) : minimum: 0 average: 1.5153
***Cells with small determinant found, number of cells: 1888
<<Writing 1888 under-determined cells to set underdeterminedCells
Concave cell check OK.

Failed 1 mesh checks.

End

What could I do for my mesh? Could be this the cause of my problems with iterations?
thak you

wyldckat October 23, 2012 15:08

Hi Francesco,

From what I can discern, these two are common on both checks:
Quote:

Originally Posted by Bombolati (Post 388059)
(...)

Face-face connectivity OK.
<<Writing 576 cells with with two non-boundary faces to set twoInternalFacesCells

(...)

Cell determinant (wellposedness) : minimum: 0 average: 1.5153
***Cells with small determinant found, number of cells: 1888
<<Writing 1888 under-determined cells to set underdeterminedCells
Concave cell check OK.

(...)

The first one almost looks like baffles are not properly defined. The second is a real source of concern, because the minimum determinant is 0! I think that means that the cells are not properly defined and could be corrupting your case!

Currently I'm not aware of any tools for OpenFOAM that can properly help you fix the mesh. You could try modifyMesh for manipulating the mesh, but I'm not aware of any tutorial that shows how it's used. The other hypothesis would be to use setSet + subsetMesh to removed the damaged cells (described here http://openfoamwiki.net/index.php/SetSet#Usage_example), but that's not a very good idea either.

Like I wrote in the previous mesh: either you redo the mesh again, with better options; or you can try polyDualMesh.

Last but not least, if you must recover this damaged mesh and the data there-in, then you could also try the official OpenFOAM support: http://www.openfoam.com/support/software.php - or any other company that provides support for it, as indicated in the main page of the openfoamwiki.net: http://openfoamwiki.net/index.php/Ma...cial_Companies

Good luck!
Bruno

Bombolati October 26, 2012 04:34

Hi Bruno and at all foamers!
In this days I had time to think the best way to solve my problem. I think to open my mesh in fluent only to do a reorder domain and a reorder zones. After I should export the mesh in ASCII mode. The questions are:

1) could I have some hopes to solve the problem in this way?

2) If I do the previous steps to my mesh, the conversion gives me a file that has just 100 MB dimension when the starting file size is almost 800MB, why?

The proof that something is wrong is that this converted file is unreadable by the foam3DmeshToFoam utility that gives me an error about the kind of file that it is reading.

Thank you very much for every ideas!


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