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twoLiquidMixingFoam: alpha becomes unbounded

Hi.
I get an alpha at 1.6.
I think alpha is supposed to be bounded between 0 and 1.
I have the following settings in fvSolutions:

Code:

"alpha.water.*"

    {

        nAlphaCorr      1;

        nAlphaSubCycles 2;

        cAlpha          1;

        icAlpha         0; 



        MULESCorr       yes;

        nLimiterIter    10;

        alphaApplyPrevCorr  yes;



        solver          smoothSolver;

        smoother        symGaussSeidel;

        tolerance       1e-8;

        relTol          0;

        minIter         1;

    }

Does anybody have an idea about how to solve this?

This is far to less information. We need your case for telling something valuable.

Quote:

Originally Posted by piu58 (Post 686315)

This is far to less information. We need your case for telling something valuable.

Hi.
Maybe a picture can explain the case somewhat. The following shows my alpha, scaled from 1 to its max value (so the problem area shows easily)

Attachment 62304

It is a flow of two fluids in a tank, and there is an obstacle at the top.
The flow is going from right to left.

Edit: I might add that the phase equal to 1 is at the bottom, so the part that is larger than 1 comes from nowhere.

Maybe not relevant, but in case:
The top BC for U infront of the obstacle is "inletOutlet" with internalField. In practice only the zeroGradient part is activiated in this area, since the flow goes up. The rest of the top as slip BC. This is a result of lots of trial and error. Slip over the whole does not work (Get blowup at a single cell at the corner of the obstacle infront cloeses to the screenm which is a symmetryPlane side). Inlet outlet over the full top gave very strange results.