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Too many iterations in pimplefoam and extreme Courant Number

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Old   December 21, 2020, 11:58
Default Too many iterations in pimplefoam and extreme Courant Number
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Hi, I'm running a simulation in OF8 about air running into two chambers, and the second chamber is with desks and windows (outlets), and when I start the simulation I don't know why Courant Number goes very high and Pimple iterations for velocity goes very high (1000 iterations!) .
Here are my docs about the case:
fvSchemes
Quote:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 8 |
| \\ / A nd | Website: www.openfoam.com |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object fvSchemes;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

ddtSchemes
{
default Euler;
}

gradSchemes
{
default Gauss linear;
}

divSchemes
{
default none;
div(U) Gauss linear;
div(phi,U) Gauss linearUpwind grad(U);
div(phi,k) Gauss linearUpwind grad(U);
div(phi,K) Gauss linearUpwind grad(U);
div(phi,epsilon) Gauss linearUpwind grad(U);
div((nuEff*dev2(T(grad(U))))) Gauss linear;
}

laplacianSchemes
{
default Gauss linear corrected;
}

interpolationSchemes
{
default linear;
}

snGradSchemes
{
default corrected;
}

wallDist
{
method meshWave;
}


// ************************************************** *********************** //
fvSolution
Quote:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 8 |
| \\ / A nd | Website: www.openfoam.com |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

solvers
{
"(p|pcorr)"
{
solver GAMG;
smoother DICGaussSeidel;
tolerance 1e-06;
relTol 0.1;
}
"(p|pcorr)Final"
{
$p;
tolerance 1e-06;
relTol 0;
}
"(U|k|epsilon)"
{
solver smoothSolver;
smoother symGaussSeidel;
tolerance 1e-06;
relTol 0.1;
}
"(U|k|epsilon)Final"
{
$U;
tolerance 1e-06;
relTol 0;
}
}


PIMPLE
{
momentumPredictor yes;
nOuterCorrectors 3;
nCorrectors 1;
nNonOrthogonalCorrectors 0;
}

// ************************************************** *********************** //
controlDict
Quote:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 8 |
| \\ / A nd | Website: www.openfoam.com |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
location "system";
object controlDict;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

application pimpleFoam;

startFrom latestTime;

startTime 0;

stopAt endTime;

endTime 100;

deltaT 0.01;

writeControl adjustableRunTime;

writeInterval 0.1;

purgeWrite 0;

writeFormat ascii;

writePrecision 7;

writeCompression no;

timeFormat general;

timePrecision 6;

runTimeModifiable yes;

adjustTimeStep yes;

maxCo 1;

maxDeltaT 1;

// ************************************************** *********************** //
Thanks in advance!
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Old   December 21, 2020, 17:44
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Can you post the terminal output from the run? It's difficult to know what's failing without more detail. I have had similar issues in the past due to poorly configured pressure boundary conditions. Can you post your velocity and pressure files for time 0?
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Old   December 21, 2020, 17:56
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Yes, this is the U file
Quote:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 8 |
| \\ / A nd | Website: www.openfoam.com |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volVectorField;
location "0";
object U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform (0 0 0);

boundaryField
{


door
{
type fixedValue;
value uniform (0.017 0 0);
}
outlet
{
type pressureInletOutletVelocity;
value uniform (0 0 0);
}
room
{
type noSlip;
}
desk
{
type noSlip;
}
}

// ************************************************** *********************** //
the p file
Quote:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 8 |
| \\ / A nd | Website: www.openfoam.com |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0;

boundaryField
{


door
{
type fixedFluxPressure;
value uniform 0;
}
outlet
{
type fixedValue;
value uniform 0;
}
room
{
type fixedFluxPressure;
value uniform 0;
}
desk
{
type fixedFluxPressure;
value uniform 0;
}
}

// ************************************************** *********************** //
and finally the output from terminal
Quote:
smoothSolver: Solving for Uy, Initial residual = 0.6509285, Final residual = 0.1032544, No Iterations 1000
smoothSolver: Solving for Uz, Initial residual = 0.7323367, Final residual = 0.07074074, No Iterations 11
GAMG: Solving for p, Initial residual = 0.07494196, Final residual = 9.292237e-07, No Iterations 20
time step continuity errors : sum local = 4.686679e-08, global = -1.198138e-08, cumulative = -1.194553e-08
PIMPLE: Iteration 3
smoothSolver: Solving for Ux, Initial residual = 0.8361626, Final residual = 0.001106414, No Iterations 1000
smoothSolver: Solving for Uy, Initial residual = 0.8377132, Final residual = 0.008449529, No Iterations 1000
smoothSolver: Solving for Uz, Initial residual = 0.7910758, Final residual = 0.02389388, No Iterations 1000
GAMG: Solving for p, Initial residual = 0.04923039, Final residual = 8.084387e-07, No Iterations 21
time step continuity errors : sum local = 2.232614e-07, global = 5.027081e-08, cumulative = 3.832528e-08
smoothSolver: Solving for epsilon, Initial residual = 0.9992263, Final residual = 0.4835003, No Iterations 1000
bounding epsilon, min: -7.34624e-10 max: 995.1444 average: 6.346123
smoothSolver: Solving for k, Initial residual = 0.9973013, Final residual = 0.4522163, No Iterations 1000
bounding k, min: -3.143589e-05 max: 1065320 average: 5459.827
ExecutionTime = 210.48 s ClockTime = 213 s

Courant Number mean: 0.2754559 max: 95.37229
deltaT = 2.545671e-05
Time = 0.254653

PIMPLE: Iteration 1
smoothSolver: Solving for Ux, Initial residual = 0.9099291, Final residual = 0.08523419, No Iterations 11
smoothSolver: Solving for Uy, Initial residual = 0.8989947, Final residual = 0.08899617, No Iterations 11
smoothSolver: Solving for Uz, Initial residual = 0.9037813, Final residual = 0.08908715, No Iterations 11
GAMG: Solving for p, Initial residual = 0.7842777, Final residual = 8.843572e-07, No Iterations 24
time step continuity errors : sum local = 4.948967e-10, global = 4.459951e-11, cumulative = 3.836988e-08
PIMPLE: Iteration 2
smoothSolver: Solving for Ux, Initial residual = 0.6638426, Final residual = 0.06044681, No Iterations 4
smoothSolver: Solving for Uy, Initial residual = 0.7162897, Final residual = 0.06805736, No Iterations 4
smoothSolver: Solving for Uz, Initial residual = 0.4622216, Final residual = 0.0425732, No Iterations 14
GAMG: Solving for p, Initial residual = 0.508095, Final residual = 5.898441e-07, No Iterations 13
time step continuity errors : sum local = 0.0001096816, global = 1.247257e-05, cumulative = 1.251094e-05
PIMPLE: Iteration 3
smoothSolver: Solving for Ux, Initial residual = 0.8269592, Final residual = 4.963339e-05, No Iterations 1000
smoothSolver: Solving for Uy, Initial residual = 0.8753593, Final residual = 4.497802e-05, No Iterations 1000
smoothSolver: Solving for Uz, Initial residual = 0.9537568, Final residual = 0.008914428, No Iterations 1000
GAMG: Solving for p, Initial residual = 0.08466316, Final residual = 8.137131e-07, No Iterations 17
time step continuity errors : sum local = 0.0009854679, global = 7.101718e-05, cumulative = 8.352812e-05
smoothSolver: Solving for epsilon, Initial residual = 0.07152224, Final residual = 7.295898e-06, No Iterations 1000
smoothSolver: Solving for k, Initial residual = 0.5589747, Final residual = 0.2559312, No Iterations 1000
bounding k, min: -7.986735e-08 max: 3.936735e+13 average: 4.229692e+10
ExecutionTime = 265.85 s ClockTime = 269 s

Courant Number mean: 423.4989 max: 297771.9
deltaT = 8.549065e-11
Time = 0.254653

PIMPLE: Iteration 1
smoothSolver: Solving for Ux, Initial residual = 0.7955269, Final residual = 0.07929837, No Iterations 52
smoothSolver: Solving for Uy, Initial residual = 0.8229975, Final residual = 0.08114433, No Iterations 8
smoothSolver: Solving for Uz, Initial residual = 0.82031, Final residual = 0.08193973, No Iterations 68
GAMG: Solving for p, Initial residual = 0.9757602, Final residual = 7.160156e-07, No Iterations 20
time step continuity errors : sum local = 3.740796e-09, global = -8.817044e-10, cumulative = 8.352724e-05
PIMPLE: Iteration 2
smoothSolver: Solving for Ux, Initial residual = 0.7606829, Final residual = 0.1359182, No Iterations 1000
smoothSolver: Solving for Uy, Initial residual = 0.6933683, Final residual = 0.3155372, No Iterations 1000
smoothSolver: Solving for Uz, Initial residual = 0.619054, Final residual = 0.06190353, No Iterations 752
GAMG: Solving for p, Initial residual = 0.5403974, Final residual = 6.965992e-07, No Iterations 11
time step continuity errors : sum local = 0.02229625, global = 0.004422845, cumulative = 0.004506373
PIMPLE: Iteration 3
smoothSolver: Solving for Ux, Initial residual = 0.9992559, Final residual = 0.00130093, No Iterations 1000
smoothSolver: Solving for Uy, Initial residual = 0.9949462, Final residual = 0.01055557, No Iterations 1000
smoothSolver: Solving for Uz, Initial residual = 0.9985097, Final residual = 0.0008934067, No Iterations 1000
GAMG: Solving for p, Initial residual = 0.2658656, Final residual = 5.074425e-07, No Iterations 11
time step continuity errors : sum local = 0.7461154, global = -0.07991379, cumulative = -0.07540742
[3] #0 Foam::error:rintStack(Foam::Ostream&) at ??:?
[3] #1 Foam::sigFpe::sigHandler(int) at ??:?
[3] #2 ? in "/lib/x86_64-linux-gnu/libc.so.6"
[3] #3 Foam::smoothSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
[3] #4 Foam::fvMatrix<double>::solveSegregated(Foam::dict ionary const&) at ??:?
[3] #5 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/pimpleFoam"
[3] #6 Foam::fvMatrix<double>::solve() in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/pimpleFoam"
[3] #7 Foam::SolverPerformance<double> Foam::solve<double>(Foam::tmp<Foam::fvMatrix<doubl e> > const&) at ??:?
[3] #8 Foam::RASModels::kEpsilon<Foam::IncompressibleMome ntumTransportModel<Foam::transportModel> >::correct() at ??:?
[3] #9 ? in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/pimpleFoam"
[3] #10 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
[3] #11 ? in "/opt/openfoam8/platforms/linux64GccDPInt32Opt/bin/pimpleFoam"
[jcano-VirtualBox:57756] *** Process received signal ***
[jcano-VirtualBox:57756] Signal: Floating point exception (8)
[jcano-VirtualBox:57756] Signal code: (-6)
[jcano-VirtualBox:57756] Failing at address: 0x3e80000e19c
[jcano-VirtualBox:57756] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x46210)[0x7febda57b210]
[jcano-VirtualBox:57756] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0xcb)[0x7febda57b18b]
[jcano-VirtualBox:57756] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x46210)[0x7febda57b210]
[jcano-VirtualBox:57756] [ 3] /opt/openfoam8/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so(_ZNK4Foam12smoothSolver5solveERNS_5 FieldIdEERKS2_h+0x4e8)[0x7febdafbac18]
[jcano-VirtualBox:57756] [ 4] /opt/openfoam8/platforms/linux64GccDPInt32Opt/lib/libfiniteVolume.so(_ZN4Foam8fvMatrixIdE15solveSegr egatedERKNS_10dictionaryE+0x18b)[0x7febdd1a275b]
[jcano-VirtualBox:57756] [ 5] pimpleFoam(_ZN4Foam8fvMatrixIdE5solveERKNS_10dicti onaryE+0x1e8)[0x55e5776b62e8]
[jcano-VirtualBox:57756] [ 6] pimpleFoam(_ZN4Foam8fvMatrixIdE5solveEv+0x120)[0x55e5776b6590]
[jcano-VirtualBox:57756] [ 7] /opt/openfoam8/platforms/linux64GccDPInt32Opt/lib/libincompressibleMomentumTransportModels.so(_ZN4Fo am5solveIdEENS_17SolverPerformanceIT_EERKNS_3tmpIN S_8fvMatrixIS2_EEEE+0x41)[0x7febdde8c881]
[jcano-VirtualBox:57756] [ 8] /opt/openfoam8/platforms/linux64GccDPInt32Opt/lib/libincompressibleMomentumTransportModels.so(_ZN4Fo am9RASModels8kEpsilonINS_36IncompressibleMomentumT ransportModelINS_14transportModelEEEE7correctEv+0x 89f)[0x7febddf0998f]
[jcano-VirtualBox:57756] [ 9] pimpleFoam(+0x2f56c)[0x55e57766556c]
[jcano-VirtualBox:57756] [10] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf3)[0x7febda55c0b3]
[jcano-VirtualBox:57756] [11] pimpleFoam(+0x313fe)[0x55e5776673fe]
[jcano-VirtualBox:57756] *** End of error message ***
--------------------------------------------------------------------------
Primary job terminated normally, but 1 process returned
a non-zero exit code. Per user-direction, the job has been aborted.
--------------------------------------------------------------------------
--------------------------------------------------------------------------
mpirun noticed that process rank 3 with PID 0 on node jcano-VirtualBox exited on signal 8 (Floating point exception).
--------------------------------------------------------------------------
^C
[1]+ Exit 136 mpirun -np 4 pimpleFoam -parallel > log
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Old   December 21, 2020, 18:25
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hmm, It looks to me to be failing on a Div/0 error while calculating epsilon. I notice in your solution file you have the relative tolerance for U|K|epsilon set to 0. I don't think this is the issue but try setting it to 0.1 and see if it solves.

For your pressure boundaries try setting your door, room, and desk to zeroGradient rather than fixed flux pressure and see if it helps.
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Old   December 21, 2020, 18:41
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I tried to change to zeroGradient in pressure and I get this message:
Quote:
[3]
[3] --> FOAM FATAL IO ERROR:
[3] Unable to set reference cell for field p
Please supply either pRefCell or pRefPoint
[3]
[3]
[3] file: IOstream/PIMPLE from line 0 to line 0.
[3]
[3] From function bool Foam::setRefCell(const volScalarField&, const volScalarField&, const Foam::dictionary&, Foam::label&, Foam::scalar&, bool)
[3] in file cfdTools/general/findRefCell/findRefCell.C at line 102.
[3]
FOAM parallel run exiting
[3] [0]
[0]
[0] --> FOAM FATAL IO ERROR:
[0] Unable to set reference cell for field p
Please supply either pRefCell or pRefPoint
[0]
[0]
[0] file: /media/sf_carpetacompartida/jcano-8/run/tfg_s1_3_1/system/fvSolution/PIMPLE from line 51 to line 54.
[0]
[0] From function bool Foam::setRefCell(const volScalarField&, const volScalarField&, const Foam::dictionary&, Foam::label&, Foam::scalar&, bool)
[0] in file cfdTools/general/findRefCell/findRefCell.C at line 102.
[0]
FOAM parallel run exiting
[0]
[1]
[1]
[1] --> FOAM FATAL IO ERROR:
[1] Unable to set reference cell for field p
Please supply either pRefCell or pRefPoint
[1]
[1]
[1] file: IOstream/PIMPLE from line 0 to line 0.
[1]
[1] From function bool Foam::setRefCell(const volScalarField&, const volScalarField&, const Foam::dictionary&, Foam::label&, Foam::scalar&, bool)
[1] in file cfdTools/general/findRefCell/findRefCell.C at line 102.
[1]
FOAM parallel run exiting
[1]


[2]
[2] --------------------------------------------------------------------------
MPI_ABORT was invoked on rank 3 in communicator MPI COMMUNICATOR 3 SPLIT FROM 0
with errorcode 1.

NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.
You may or may not see output from other processes, depending on
exactly when Open MPI kills them.
--------------------------------------------------------------------------
--> FOAM FATAL IO ERROR:
[2] Unable to set reference cell for field p
Please supply either pRefCell or pRefPoint
[2]
[2]
[2] file: IOstream/PIMPLE from line 0 to line 0.
[2]
[2] From function bool Foam::setRefCell(const volScalarField&, const volScalarField&, const Foam::dictionary&, Foam::label&, Foam::scalar&, bool)
[2] in file cfdTools/general/findRefCell/findRefCell.C at line 102.
[2]
FOAM parallel run exiting
[2]
[jcano-VirtualBox:60682] PMIX ERROR: UNREACHABLE in file ../../../src/server/pmix_server.c at line 2193
[jcano-VirtualBox:60682] 3 more processes have sent help message help-mpi-api.txt / mpi-abort
[jcano-VirtualBox:60682] Set MCA parameter "orte_base_help_aggregate" to 0 to see all help / error messages
top
I'm very new in OpenFoam and I don't understand it too much, thanks in advance
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Old   December 21, 2020, 18:52
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Try modifying your fvSolution file to include the reference pressure like this:

PIMPLE
{
momentumPredictor yes;
nOuterCorrectors 3;
nCorrectors 1;
nNonOrthogonalCorrectors 0;
pRefCell 0;
pRefValue 0;
}

from this:

PIMPLE
{
momentumPredictor yes;
nOuterCorrectors 3;
nCorrectors 1;
nNonOrthogonalCorrectors 0;
}
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Old   December 21, 2020, 19:01
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Thanks, now it says that I should check my velocity boundary conditions as it's stated here:
Quote:
[3] --> FOAM FATAL ERROR:
[3] Continuity error cannot be removed by adjusting the outflow.
Please check the velocity boundary conditions and/or run potentialFoam to initialise the outflow.
Total flux : 0.006346041
Specified mass inflow : 0.3029468
Specified mass outflow : 0
Adjustable mass outflow : 0
[3]
[3]
[3] From function bool Foam::adjustPhi(Foam::surfaceScalarField&, const volVectorField&, Foam::volScalarField&)
[3] in file cfdTools/general/adjustPhi/adjustPhi.C at line [0] [1]
[1]
[1] --> FOAM FATAL ERROR:
[1] Continuity error cannot be removed by adjusting the outflow.
Please check the velocity boundary conditions and/or run potentialFoam to initialise the outflow.
Total flux : 0.006346041
Specified mass inflow : 0.3029468
Specified mass outflow : 0
Adjustable mass outflow : 0
I changed the outlet velocity boundary condition to be calculated but still the same error.
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Old   December 21, 2020, 19:12
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mmmm, well I am not super confident on this one but I suspect it may be due to your 0 pressure condition in your solution resulting in no mass flow at your outlet. if you set the outlet pressure to fixed uniform 100,000 and the internal field uniform to 100,000 in your pressure boundary file does it fix the problem? this would be equivalent to 1Bar pressure (atmospheric) for both the outlet condition and the initial condition.
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Old   December 21, 2020, 19:21
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Yeah,but I don't now where I see if you put 0 in the pressure file it's equal to atmospheric pressure and on the other hand I think in pimpleFoam it's not very important pressure but p/density it is.
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Old   December 21, 2020, 19:38
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Oh you're right, it's dynamic pressure so it shouldn't matter. For some reason it is setting your mass outflow to 0, not sure if this could be an issue with the way the outlet is defined, the pressureInletOutletVelocity should work unless it is considering the outflow to be backwards and limiting it to zero. will it execute if you set the outlet velocity boundary to zeroGradient?
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Old   December 21, 2020, 19:44
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Same as before if I set the velocity boundary condition in the outlet as zeroGradient.
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Old   December 21, 2020, 19:47
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hmm, sounds like it could be an issue with the boundary definition. can you go into the constant/polymesh/boundary file and post the contents?
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Old   December 21, 2020, 19:51
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Yes, here it is
Quote:
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 8
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class polyBoundaryMesh;
location "constant/polyMesh";
object boundary;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

4
(
door
{
type patch;
nFaces 28084;
startFace 1821493;
}
outlet
{
type patch;
nFaces 13500;
startFace 1849577;
}
room
{
type wall;
inGroups List<word> 1(wall);
nFaces 121320;
startFace 1863077;
}
desk
{
type wall;
inGroups List<word> 1(wall);
nFaces 17684;
startFace 1984397;
}
)

// ************************************************** *********************** //
Also the checkMesh if it's something wrong with the quality of it I think the mesh is fine.
Quote:
Mesh stats
points: 775187
faces: 2002081
internal faces: 1821493
cells: 613614
faces per cell: 6.231237
boundary patches: 4
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 565302
prisms: 1068
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 47244
Breakdown of polyhedra by number of faces:
faces number of cells
5 16
6 2338
9 42246
12 2520
15 124

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
door 28084 28441 ok (non-closed singly connected)
outlet 13500 13908 ok (non-closed singly connected)
room 121320 122634 ok (non-closed singly connected)
desk 17684 17860 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (0.1649997 0.008503071 0.00999999) (15.645 2.99 5.99)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (1.564987e-14 4.628244e-15 -4.244613e-15) OK.
Max cell openness = 3.904498e-16 OK.
Max aspect ratio = 5.813497 OK.
Minimum face area = 0.0001074356. Maximum face area = 0.01207598. Face area magnitudes OK.
Min volume = 1.705371e-06. Max volume = 0.001253467. Total volume = 263.677. Cell volumes OK.
Mesh non-orthogonality Max: 48.42884 average: 8.295771
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 2.965011 OK.
Coupled point location match (average 0) OK.

Mesh OK.

End
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Old   December 21, 2020, 20:11
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Looks like it should be fine. I am really not sure what is going on, as far as I can see your configuration should work fine. How big is the simulation setup? are you able to zip and upload it?
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Old   December 22, 2020, 10:24
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Yes, here are the different folders except the constant folder I can't upload it.0 (cÚpia).zip

system (cÚpia).zip


Thanks in advance.
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Old   December 25, 2020, 17:26
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Hi,
I have the same issue in my case. pimplefoam converges but the courant number increases to very high values even in the first time steps. It seems that the resulted U values are incorrectly very high which lead to high Co#.
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Old   September 8, 2023, 05:52
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Hi,


I ever faced a similar issue. Try setting up proper initial fields. It helps in stability a lot. 0 is a poor initial condition.
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