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-   -   How to solve this alpha Eqn using MULES? (http://www.cfd-online.com/Forums/openfoam-solving/124197-how-solve-alpha-eqn-using-mules.html)

keepfit September 29, 2013 14:44

How to solve this alpha Eqn using MULES?
 
Hi Foamers,

I want to modify the interFoam solver where the alpha Eqn is like:

Eqn 1:
http://24.media.tumblr.com/6c11fdf1e...saho2_1280.png

The fluid Cell contains fluid phase 1 and phase 2, along with the solid phase, here \epsilon_f stands for the volume fraction occupied by fluid (V_phase1 + V_phase2).

\epsilon_f filed is also defined in createFields.H
Code:

    volScalarField voidfractionFluid
    (
        IOobject
        (
            "voidfractionFluid",
            runTime.timeName(),
            mesh,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        mesh
    );

The original VOF method in interFoam is:

Eqn 2:
http://25.media.tumblr.com/a69766b4c...saho1_1280.png
the implementation code of alpha equation:

Code:


 for (int aCorr=0; aCorr<nAlphaCorr; aCorr++)
    {
        surfaceScalarField phiAlpha
        (
            fvc::flux
            (
                phi,
                alpha1,
                alphaScheme
            )
          + fvc::flux
            (
                -fvc::flux(-phir, scalar(1) - alpha1, alpharScheme),
                alpha1,
                alpharScheme
            )
        );

        MULES::explicitSolve(alpha1, phi, phiAlpha, 1, 0);

        rhoPhi = phiAlpha*(rho1 - rho2) + phi*rho2;

So I wonder how to add the volScalarField voidfractionFluid to the MULES solver similar like above? Any hints will be highly appreciated!

Cheers,

David Long

santiagomarquezd October 11, 2013 13:36

Hi, I guess it could be done using the source term included in MULES.

Regards.

Mahdi2010 October 23, 2013 04:06

Hi Santiago
I followed your PhD thesis where you explain how MULE works. Concerning this problem
how the source terms should look like? because MULE needs Su and Sp source terms
to solve it implicitly or explicitly, but the question is how to derive Su and Sp from this source term on the right hand side.

gaza July 11, 2015 05:57

Hi Mahdi
Try to read this post
http://www.cfd-online.com/Forums/ope...-equation.html


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