[smog]

Hello all, I am doing an incompressible, multiphase simulation of a water jet shooting into a cylinder containing stagnant air. I am using interFoam solver. I have refined the grid to have the minimum base cell dimension of 0.2 mm. I am having a really hard time :
1) Getting the solution to stay stable (there are severe spurious velocities in the internal field), whenever I use any 2nd order divergence schemes. I used Gauss linearUpwind grad (U), Gauss vanLeerV 1, Gauss limitedLinearV 1. None of them stop my simulation from blowing up.

2) On a coarser mesh, I can get some simulations to run without blowing up, but the water jet shoots through the domain without showing any signs of break-up. Just a straight beam-like behaviour.

I have come to believe I am doing something wrong with the IC/BCs. Here are my files, I have changed them recently, let me know if they make sense in the context of the problem.



k:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object k;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 1.5;

boundaryField
{
inflow
{
type turbulentIntensityKineticEnergyInlet;
intensity 0.05;
value uniform 1.5;
//type fixedValue;
//value uniform 1.5; // calculated as per [1.5*pow(U*I,2)], U = mean flow velocity, I = turbulence intensity (assumed 5%)
}
outflow
{
type inletOutlet;
inletValue uniform 1.5;
value uniform 1.5;
//type zeroGradient;
}
wall_imported
{
type kqRWallFunction; // Average y+ = 30
value uniform 1.5;
}
inoutflow
{
type fixedValue;
value uniform 0; // No BL on this patch
}
"proc.*"
{
type processor;
value uniform 0;
}
}


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


nut:

/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object nut;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0; // can be calculated = 1.4e-04, as per [sqrt(3/2)*(U*I*l)], I = turb intensity (assumed 10%), l = turb length scale

boundaryField
{
inflow
{
type calculated;
value uniform 0;
}
outflow
{
type calculated;
value uniform 0;
}
wall_imported
{
type nutkWallFunction; // Average y+ = 30
value uniform 0;
}
inoutflow
{
type fixedValue;
value uniform 0; // No BL on this patch
}
"proc.*"
{
type processor;
value uniform 0;
}
}


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

Omega:

/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object omega;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 1e04;

boundaryField
{
inflow
{
type fixedValue;
value uniform 1e04; // clculated as per [sqrt(k)/l], k = turbulence kinetic energy, l = turbulence length scale = (0.038*D) for pipe flows
}
outflow
{
type inletOutlet;
inletValue uniform 1e04;
value uniform 1e04;
//type zeroGradient;
}
wall_imported
{
type omegaWallFunction; // Average y+ = 30
value uniform 1e04;
}
inoutflow
{
type fixedValue;
value uniform 0; // No BL on this patch
}
"proc.*"
{
type processor;
value uniform 0;
}
}


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

p_org:
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object p_org;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0;

boundaryField
{
inflow
{
type zeroGradient;
}
outflow
{
type fixedValue;
value uniform 0;
}
wall_imported
{
type zeroGradient;
}
inoutflow
{
type zeroGradient;
}
"proc.*"
{
type processor;
value uniform 0;
}
}


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

U:

/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ 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
{
inflow
{
type flowRateInletVelocity;
massFlowRate constant 0.1;
value uniform (0 0 0);
//type fixedValue;
//value uniform (-20 0 0);
}
outflow
{
type pressureInletOutletVelocity;
value uniform (0 0 0);
inletValue uniform (0 0 0);
//type zeroGradient;
}
wall_imported
{
type fixedValue;
value uniform (0 0 0);
}
inoutflow
{
type fixedValue;
value uniform (0 0 0);
}
"proc.*"
{
type processor;
value uniform 0;
}
}


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






Sorry for the long post. Any comments will be highly appreciated.