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Boussinesq equation of state combined with polynomial viscosity

Hi,

I'd like to solve a case where fluid density and viscosity depend on temperature. There are also some walls so I use chtMultiRegionSimpleFoam application.

When I set up thermophysical properties of the fluid like this:

Code:

thermoType

{

    type            heRhoThermo;

    mixture         pureMixture;

    transport       polynomial;

    thermo          hPolynomial;

    equationOfState Boussinesq;

    specie          specie;

    energy          sensibleEnthalpy;

}

I get FOAM FATAL ERROR: Unknown rhoTherm type, followed by listing of valid combinations. I can either use combination sutherland-janaf-Boussineq or polynomial-hPolynomial-icoPolynomial (for transport-thermo-equasionOfState respectively), however, I'd prefer not to.

Naive attempt to add another valid combination by adding

Code:

makeThermos

(

    rhoThermo,

    heRhoThermo,

    pureMixture,

    polynomialTransport,

    sensibleEnthalpy,

    hPolynomialThermo,

    Boussinesq,

    specie

);

to $FOAM_SRC/thermophysicalModels/basic/rhoThermo/rhoThermos.C did not help. Can someone explain why?

Is there a way to use combination of polynomial mu and Cp along with Boussinesq approximation?

Hi.

Did you find a proper solution to your problem?

You can use polynomial.

Code:

thermoType

{

    type            heRhoThermo;

    mixture         pureMixture;

    transport       polynomial;

    thermo          hPolynomial;

    equationOfState icoPolynomial;

    specie          specie;

    energy          sensibleInternalEnergy;

}

For the equation of state, Boussinesq equation can be approximated by a polynomial. See Peric's book on page 15,
$\rho = (\rho_0 + \rho_0 \beta T_0) - \rho_0 \beta T$

Interesting, thanks for this tip, I haven't thought of that.