[julieng]

Hello,

I try to implement a heat source to take into account the external radiation from the ambient temperature on the interface between solid to fluid regions of a very simple test case using chtMultiRegionFoam solver.

My fvOption in the /solid directory is below:

temperatureLimit
{
    type limitTemperature;
    active true;

    limitTemperatureCoeffs
    {
        selectionMode all;
        min 290;
        max 10000;
    }
}

heatSource
{
    type         scalarCodedSource;

    active       true;
    
    name         sourceTime;

  

    scalarCodedSourceCoeffs
    {
         selectionMode   all;//cellSet
         //cellSet        externalRadiationcell;
        fields        (h);
       // fieldNames (T);
        redirectType sourceTime;
      //   name sourceTime;

        codeInclude
        #{
        
        #};

        codeCorrect
        #{
            Pout<< "**codeCorrect**" << endl;
        #};

        codeAddSup
        #{
        
        
        
            const scalar rhomat = 7850;
            const scalar emi = 0.9;
            const scalar Cp = 450;
            const scalar sigma = 5.670374e-8;
            const scalar Trad = 1000;
           
        
         
            const volScalarField& T = eqn.psi();          // sans cette ligne erreur
            scalarField& hSource = eqn.source();           //defining source
            
          
            
            // Iterating through patch
                word solid_to_fluid = coeffs().lookupOrDefault<word>("patch", "solid_to_fluid");
                const fvPatch& pp = mesh().boundary()[solid_to_fluid];
                forAll(pp, i) {
                label cell_i = pp.faceCells()[i];
               scalar Ai = pp.magSf()[i];
                scalar Ts = T[cell_i];
                hSource[cell_i] = sigma*emi*(pow4(Ts)-pow4(Trad))*Ai/rhomat/Cp;
            }
         
            // Pout << V << endl; // retourne 3200 cells avec un volume de 0.00025 m3 soit 0.8m3 dans log
            // le cellSet comporte 400 cells soit 0.1 m3
            Pout << "***codeAddSup***" << endl;
            Pout << hSource << endl;
           // Pout << pp.magSf() << endl; // retourne la surface d'une cell 0.01m2
         
        #};

        codeSetValue
        #{
         //   Pout<< "**codeSetValue**" << endl;
        #};

        // Dummy entry. Make dependent on above to trigger recompilation
        code
        #{
            $codeInclude
            $codeCorrect
            $codeAddSup
            $codeSetValue
        #};
    }

    sourceTimeCoeffs
    {
         $scalarCodedSourceCoeffs;
    }
}

I have check that the selected cells surfaces where the heatsource term is applied is ok. The dimension of the heatsource is Km^2/s, I don't know if I need to have K/s or something else. I see on the forum that K/s is the correct dimension for volumic heat source.

I think that the problem is the magnitude in pow4(Ts) therm in the heatsource equation.

I have control the Ts value in the log and it seems that it is the h value instead of Temperature value with Ts=h/Cp. In consequense, my heatsource term is too large and the temperature explodes when I run the case.
I have try to put pw4(Ts/Cp) to put a temperature value inside the equation the heatsource term is too low. and the temperature of the surface is not increasing at all.
If I put the line // fieldNames (T); active, an error occurs.

I think that I am not too far the solution but as I don't understand exactly what happened I am not able to write the correct equation.

If someone knows how to resolve this, it would be very helpfull for me.

Best regards

Julien

[julieng]

Finally it works!!
Simply, I need to put W unit for the heatsource. It matches perfectly with other software.

[julieng]

Hello,

I need to monitor the value of the heatsource term added in the fvOption file.
I can see it in log file but for each cells of the patch. It is quite heavy in the log file and not very usable.
codeAddSup
#{
...
Pout << hSource << endl;
}

Is there a way to create an independant file with my hSourve values via the controlDict file or from the fvOption file ?

Best regards