[maguirre]

Hi everyone!

I'm trying to solve a case where an electric arc (represented as a zone filled with "superheated air", any electromagnetic simulation is not taken into account) heats the air inside a metal box, see attached GMSH geometry screenshot.

I'm using OpenFoam v11 (openfoam.org version 11) with foamRun application and fluid solver. Transonic option is set on. I set a heatSource at the little dot, called blastSource, which radiates with P1 model to the rest of the volume. Also, buoyancy is applied. You can see all this configuration here:

FoamFile 
{ 
    version     2.0;
    format      ascii;
    class       dictionary; 
    location    "constant"; 
    object      fvModels; 
} 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // 

volumetricHeatSource 
{ 
    type            heatSource;
    select          cellZone;
    cellZone        blastSource;
    
    q               7600000000;//1486693; 0.4*4553000 aprox. 1.8e6
}

radiationCoeffs
{
    type	    radiation;
    libs	    ("libradiationModels.so");
}

buoyancyForce
{
    type	    buoyancyForce;
}

FoamFile
{
    format      ascii;
    class       dictionary;
    location    "constant";
    object      radiationProperties;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

radiationModel  P1;

// Number of flow iterations per radiation iteration
solverFreq 10;

absorptionEmissionModel constant;

constantCoeffs
{
   absorptivity    0.5;
   emissivity      0.5;
   E               0;
}

scatterModel    none;

sootModel       none;

Around this dot, there is a surface called plasmaSurf which is applied the MarshakRadiation condition.

FoamFile
{
    format      ascii;
    class       volScalarField;
    location    "0";
    object      G;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [1 0 -3 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    back
    {
        type            zeroGradient;
    }
    front
    {
        type            zeroGradient;
    }
    bottom
    {
        type            zeroGradient;
    }
    right
    {
        type            zeroGradient;
    }
    top
    {
        type            zeroGradient;
    }
    left
    {
        type            zeroGradient;
    }
    opening
    {
        type            zeroGradient;
    }
    plasmaSurf
    {
	type		MarshakRadiation; //constantAbsorptionEmission;
	emissivityMode	lookup;
	emissivity	uniform 1.0;
	T		T;
	value		uniform 0;
    }
}

The problem is I do not see much change in the temperature profile, see Paraview attached image. I thought it could be of a wrong BC at plasmaSurf but I think InletOutletTotalTemperature is the correct choice

FoamFile
{
    format      binary;
    class       volScalarField;
    location    "0";
    object      T;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#include	"inputs"

dimensions      [0 0 0 1 0 0 0];

internalField   uniform $temperature;

boundaryField
{
    back
    {
        type            zeroGradient;
    }
    front
    {
        type            zeroGradient;
    }
    bottom
    {
        type            zeroGradient;
    }
    right
    {
        type            zeroGradient;
    }
    top
    {
        type            zeroGradient;
    }
    left
    {
        type            zeroGradient;
    }
    opening
    {
        type            zeroGradient;
    }
    plasmaSurf
    {
	type		inletOutletTotalTemperature;
	gamma		1.4;
	Qr		Qr;
	T0		uniform $temperature;
    }
}

(The code asks me for the definition of Qr, although it is always zero. I think it is because Qr is for fvDOM radiation model, still, I don't know why it is needed)

That T profile does not change much throughout the simulation (0.25 s with a 1e-06 s as deltaT), those few cells are the only ones heated. Does anyone know what could be the problem? Maybe I set wrong the radiation model? Or any BC?

Cheers,
Matias.