[lethu]

Hello,

I got this error message unsing simpleFoam but I can't understand where the error says it is from...

Can you help me please ?

Thanks !

/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  4.1                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : 4.1
Exec   : simpleFoam
Date   : May 16 2017
Time   : 14:52:58
Host   : "abc1b7de1187"
PID    : 827
Case   : /home/openfoam/run/22-bassinTestmixerVessel2D
nProcs : 1
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create mesh for time = 0


SIMPLE: no convergence criteria found. Calculations will run for 500 steps.

Reading field p

Reading field U

Reading/calculating face flux field phi

Selecting incompressible transport model Newtonian
Selecting turbulence model type RAS
Selecting RAS turbulence model kEpsilon
bounding k, min: 0 max: 1 average: 1
bounding epsilon, min: 0 max: 0 average: 0
kEpsilonCoeffs
{
    Cmu             0.09;
    C1              1.44;
    C2              1.92;
    C3              -0.33;
    sigmak          1;
    sigmaEps        1.3;
}

Creating MRF zone list from MRFProperties
    creating MRF zone: MRF1Agitateur1
    creating MRF zone: MRF2Agitateur2
No finite volume options present

#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2  ? in "/lib/x86_64-linux-gnu/libc.so.6"
#3  Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> cons                                                        t&) at ??:?
#4  Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::opera                                                        tor/<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<double, Foam::fvPatc                                                        hField, Foam::volMesh> > const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::vol                                                        Mesh> const&) at ??:?
#5  Foam::RASModels::kEpsilon<Foam::IncompressibleTurbulenceModel<Foam::transportModel> >::                                                        correctNut() at ??:?
#6  ? at ??:?
#7  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#8  ? at ??:?

[enginpower]

It seems to be some diverging problem or some division-by-zero problem.
I have the same with my case

Try to review all the boundary condition set, if they are all ok.

I can say just this.
Wait for more expert followers

[Rana shaharyar]

im getting divergence problem what does it mean. during cfd simulation.

[enginpower]

Read in the order these:
https://en.wikipedia.org/wiki/Numeri...tial_equations
https://en.wikipedia.org/wiki/Numeri...ns#Convergence
https://web.stanford.edu/class/cme30...iscussion1.pdf
http://web.mit.edu/16.90/BackUp/www/pdfs/Chapter2.pdf

[lethu]

Maybe this could help :

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  4.x                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       volVectorField;
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0 0 0);

boundaryField
{
    agitateur1
    {
        type            noSlip;
    }
	
	agitateur2
    {
        type            noSlip;
    }
	
	bassin_wall
    {
        type            noSlip;
    }

    bassin_bottom
    {
        type            noSlip;
    }

    bassin_top
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }

}

    object      p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 0;

boundaryField
{
	agitateur1
    {
        type            zeroGradient;
    }
	
	agitateur2
    {
        type            zeroGradient;
    }

    bassin_wall
    {
        type            zeroGradient;
    }
	
	bassin_bottom
    {
        type            zeroGradient;
    }

    bassin_top
    {
        type            totalPressure;
		p0              uniform 0;
    }
}

    object      k;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 1;

boundaryField
{
	agitateur1
    {
        type            kqRWallFunction;
        value           uniform 0;
    }
	
	agitateur2
    {
        type            kqRWallFunction;
        value           uniform 0;
    }

    bassin_wall
    {
        type            kqRWallFunction;
        value           uniform 0;
    }
	
	bassin_bottom
    {
        type            kqRWallFunction;
        value           uniform 0;
    }

    bassin_top
    {
        type            calculated;
        value           uniform 0;
    }
}

    object      epsilon;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 2 -3 0 0 0 0];

internalField   uniform 0;

boundaryField
{	
	agitateur1
    {
        type            epsilonWallFunction;
        value           uniform 0;
    }
	
	agitateur2
    {
        type            epsilonWallFunction;
        value           uniform 0;
    }

    bassin_wall
    {
        type            epsilonWallFunction;
        value           uniform 0;
    }
	
	bassin_bottom
    {
        type            epsilonWallFunction;
        value           uniform 0;
    }

    bassin_top
    {
        type            calculated;
        value           uniform 0;
    }
}

    object      nut;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 2 -1 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    agitateur1
    {
        type            nutkWallFunction;
        value           uniform 0;
    }
	
	agitateur2
    {
        type            nutkWallFunction;
        value           uniform 0;
    }

    bassin_wall
    {
        type            nutkWallFunction;
        value           uniform 0;
    }
	
	bassin_bottom
    {
        type            nutkWallFunction;
        value           uniform 0;
    }

    bassin_top
    {
        type            calculated;
		value           uniform 0;
    }
}

[enginpower]

At a fast look it seems you put everywhere 0 values. So what do you need to calculate if everywhere each variable is 0?

What are your real boundary conditions? And what about the real case you want to simulate? Geometry?

[lethu]

I am trying to simulate a tank full of water with some agitation at the bottom. In MFRProperties, I set two agitators.

MRF1Agitateur1
{
    cellZone    agitateur1;
    active      yes;

    // Fixed patches (by default they 'move' with the MRF zone)
    nonRotatingPatches ("(bassin_top|bassin_bottom)");

    origin    (1 0 0);
    axis      (0 0 1);
    omega     12.32;
}

MRF2Agitateur2
{
    cellZone    agitateur2;
    active      yes;

    // Fixed patches (by default they 'move' with the MRF zone)
    nonRotatingPatches ("(bassin_top|bassin_bottom)");

    origin    (-1 0 0);
    axis      (0 0 1);
    omega     12.32;
}

I guess that my "bassin_top" BC is not good (?)
Because in reality, it would be a free surface at an atmospheric pressure.

I wanted to do a steady-state and single phase simulation. I supposed that the tank is not filled during that time.

In fine, this is what I would like to observe but for now I just made a simple cylinder.

https://drive.google.com/open?id=0B7...kZaY0FzUjBIaE0

[enginpower]

Sorry,
I can't help more.

Wait for a more expert foamer!