0bf7758dd4
Co-authored-by: Niels Gjøl Jacobsen <> Co-authored-by: Konstantinos Missios <> Co-authored-by: Henning Scheufler <henning.scheufler@dlr.de> Co-authored-by: Johan Roenby <johan.roenby@gmail.com>
49 lines
1.8 KiB
C
49 lines
1.8 KiB
C
// Including porosity effects in UEqn following:
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// Jensen, B., Jacobsen, N. G., & Christensen, E. D. (2014).
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// Investigations on the porous media equations and resistance
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// coefficients for coastal structures. Coastal Engineering, 84, 56-72.
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if (porosityEnabled)
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{
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const volScalarField& porosity = tporosity.cref();
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const word porosityModel("JensenEtAl2014");
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const dictionary& dict =
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porosityProperties.subDict(porosityModel + "Coeffs");
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const dimensionedScalar alpha(dimless/dimArea, dict.get<scalar>("alpha"));
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const dimensionedScalar beta(dimless/dimLength, dict.get<scalar>("beta"));
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const dimensionedScalar d50(dimless, dict.get<scalar>("d50"));
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const dimensionedScalar KC(dimless, dict.get<scalar>("KC"));
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// Generating Darcy-Forchheimer coefficient: F = rho*U*(a + b*|U|)
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// Shoud it be mu or muEff in the equation below?
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{
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// Darcy term
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volScalarField DarcyForchheimerCoeff
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(
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alpha*sqr(1 - porosity)*mixture.mu()/sqr(porosity)/sqr(d50)
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);
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// Adding Forchheimer term
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DarcyForchheimerCoeff += rho*mag(U)
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*beta*(1 + pos(KC)*7.5/KC)*(1 - porosity)/sqr(porosity)/d50;
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// Adding Darcy-Forchheimer term as implicit source term
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UEqn += fvm::Sp(DarcyForchheimerCoeff, U);
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}
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{
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// Generating added mass force coefficient
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const dimensionedScalar gamma_p(dimless, dict.get<scalar>("gamma_p"));
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const volScalarField Cm(gamma_p*(1 - porosity));
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UEqn += Cm*fvm::ddt(rho, U);
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UEqn += Cm*MRF.DDt(rho, U);
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}
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// Dividing both matrix entries and source term by porosity to compensate
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// for the fact that the FVM cell volume averages use division by cell
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// volume V whereas only the cell pore volume, porosity*V, is accessible.
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UEqn *= scalar(1)/porosity;
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}
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