[TCS]

Hi All,

OpenFOAM 4.1

I am adding a scalar transport equation to the InterFOAM solver
$\frac{\partial c}{\partial t} + \nabla\cdot(c{\bf u})$
to track the progress of a scalar concentration field (c) which I define in setFields to be 0,1,2 initially in certain locations.

I have successfully added a standard equation in the InterFoam.C file:

fvScalarMatrix CEqn
        (
              fvm::ddt(c)
            + fvm::div(phi, c)
        );

CEqn.solve();

However, this is affected by a large amount of numerical diffusion.

I understand I need to use the MULES FCT scheme to try and solve this, as noted in Using MULES to solve transport equation with sharp interface but am unsure of how to do this.

I've tried adding the following to the alphaEqn file:

        tmp<surfaceScalarField> phiCure
        (
            fvc::flux
            (
                phi,
                c,
                alphaScheme
            )
          + fvc::flux
            (
               -fvc::flux(-phir, alpha2, alpharScheme),
                c,
                alpharScheme
            )
        );

together with

MULES::explicitSolve(c, phiCN, phiCure, 2, 0);

but this does not compile with wmake:
error: no matching function for call to ‘explicitSolve(Foam::volScalarField&, Foam::tmp<Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> >&, Foam::tmp<Foam::GeometricField<double, Foam::fvsPatchField, Foam::surfaceMesh> >&, int, int)’
among many errors.

Any help appreciated! Cheers.

[TCS]

Any help appreciated.

[Cyp]

If you just advect a passive scalar without particular condition at the interfaces, why not just solve C from alpha? In your case you just have C=alpha.

Cheers,

[TCS]

Originally Posted by Cyp

If you just advect a passive scalar without particular condition at the interfaces, why not just solve C from alpha? In your case you just have C=alpha.

Cheers,

Hi, I've got there regions (2 droplets coalescing) of flaid. Two have the same alpha value and the issue is I need to know where one droplet is going when it coalescea with the other. So alpha gets me the outline of the two droplets together but not of each separately if you see what I mean. Because the two droplets are (currently) the same fluid. Thanks for the suggestion though

[Cyp]

When two droplets coalesce they become one... I am not sure your problem is well posed.

[Blumenkind]

I am stuck with a similar problem. Have you gotten any further?

Edit: Not a similar problem though. You were trying to compile two int, when the compiler wanted to see fields...