buoyantSimpleRadiationFoam
 

Hi All,

I am simulating the effect of natural convection inside a square cavity with radiation effects on surfaces using buoyantSimpleRadiationFoam solver. This is a 2D simulation and I am using OF 1.6.

Simulation Details:

1. The top and bottom walls are treated as adiabatic. The wall on the left, the hot wall has a specified temperature of 373 K, while the wall on the left, the cold wall, as well as the air inside the cavity have a temperature of 323 K.

I am getting uniform pressure over the whole cavity and resulting zero velocity everywhere. So. there is no convection. This does not look correct but I am not able to find out my mistake. My initial/boundary conditions are pasted below, please help me to figure out the problem with my setup.

Thanks for any help!

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object alphat;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0;

boundaryField
{
topwall
{
type compressible::alphatWallFunction;
Prt 0.85;
value uniform 0;
}
bottomwall
{
type compressible::alphatWallFunction;
Prt 0.85;
value uniform 0;
}
rightwall
{
type compressible::alphatWallFunction;
Prt 0.85;
value uniform 0;
}
leftwall
{
type compressible::alphatWallFunction;
Prt 0.85;
value uniform 0;
}
frontAndBack
{
type empty;
}
}


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

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object epsilon;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0.01;

boundaryField
{
topwall
{
type zeroGradient;

}
bottomwall
{
type zeroGradient;

}
rightwall
{
type zeroGradient;

}
leftwall
{
type zeroGradient;

}
frontAndBack
{
type empty;
}
}


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

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object G;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0;

boundaryField
{
topwall
{
type MarshakRadiation;
T T;
emissivity 1;
value uniform 0;
}

bottomwall
{
type MarshakRadiation;
T T;
emissivity 1;
value uniform 0;
}

rightwall
{
type MarshakRadiation;
T T;
emissivity 1;
value uniform 0;
}

leftwall
{
type MarshakRadiation;
T T;
emissivity 1;
value uniform 0;
}
frontAndBack
{
type empty;
}
}

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

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object k;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0.1;

boundaryField
{
topwall
{
type zeroGradient;
}
bottomwall
{
type zeroGradient;
}
rightwall
{
type zeroGradient;
}
leftwall
{
type zeroGradient;
}
frontAndBack
{
type empty;
}
}


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

FoamFile
{
version 2.0;
format ascii;
class volVectorField;
object U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform (0 0 0);

boundaryField
{
topwall
{
type fixedValue;
value uniform (0 0 0);
}

bottomwall
{
type fixedValue;
value uniform (0 0 0);
}

rightwall
{
type fixedValue;
value uniform (0 0 0);
}

leftwall
{
type fixedValue;
value uniform (0 0 0);
}
frontAndBack
{
type empty;
}
}

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

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object T;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 0 0 1 0 0 0];

internalField uniform 323.0;

boundaryField
{
rightwall
{
type fixedValue;
value uniform 323.0;
}

leftwall
{
type fixedValue;
value uniform 373.0;
}

topwall
{
type zeroGradient;
}

bottomwall
{
type zeroGradient;
}
frontAndBack
{
type empty;
}
}

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

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 100000;

boundaryField
{
topwall
{
type buoyantPressure;
value uniform 100000;
}

bottomwall
{
type buoyantPressure;
value uniform 100000;
}

rightwall
{
type buoyantPressure;
value uniform 100000;
}

leftwall
{
type buoyantPressure;
value uniform 100000;
}
frontAndBack
{
type empty;
}
}

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

FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object mut;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField uniform 0;

boundaryField
{
topwall
{
type mutWallFunction;
Cmu 0.09;
kappa 0.4187;
E 9.0;
value uniform 0;
}
bottomwall
{
type mutWallFunction;
Cmu 0.09;
kappa 0.4187;
E 9.0;
value uniform 0;
}
rightwall
{
type mutWallFunction;
Cmu 0.09;
kappa 0.4187;
E 9.0;
value uniform 0;
}
leftwall
{
type mutWallFunction;
Cmu 0.09;
kappa 0.4187;
E 9.0;
value uniform 0;
}
frontAndBack
{
type empty;
}
}


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