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B.C.:externalWallHeatFluxTemperature - different treatment of inand out heatflux?

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Old   February 21, 2014, 16:36
Default B.C.:externalWallHeatFluxTemperature - different treatment for in and out heatflux
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Hello Foamers,

I took a look at the source code of B.C.externalWallHeatFluxTemperature

and I find that there is a different treatment for inflow heat flux and outflow heat flux.

Does anybody know the theory behind this?

Thanks.

The code is copied here:

Code:
    if (oldMode_ == fixedHeatFlux)
    {
        q = q_;
    }
    else if (oldMode_ == fixedHeatTransferCoeff)
    {
        q = (Ta_ - *this)*h_;
    }
    else
    {
        FatalErrorIn
        (
            "externalWallHeatFluxTemperatureFvPatchScalarField"
            "::updateCoeffs()"
        )   << "Illegal mode " << operationModeNames[oldMode_]
            << exit(FatalError);
    }


    forAll (*this, i)
    {
        if (q[i] > 0) //in
        {
            this->refGrad()[i] = q[i]/KWall[i];
            this->refValue()[i] = 0.0;
            this->valueFraction()[i] = 0.0;
        }
        else //out
        {
            this->refGrad()[i] = 0.0;
            this->refValue()[i] = q[i]/KDelta[i] + patchInternalField()()[i];
            this->valueFraction()[i] = 1.0;
        }
    }

Last edited by wc34071209; February 22, 2014 at 09:32.
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Old   February 22, 2014, 09:32
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It seems when heat flux is in a fixedGradient b.c. is applied, whereas when heat flux is out, a fixedValue b.c. is applied.

I am totally confused for what reasons OF employs such a strategy.
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Old   February 26, 2014, 08:19
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nobody is interested? I am eager to know.
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