CFD Online Discussion Forums - Negative values for minimum alphas

Hi all,

I am using compressibleInterFoam solver to model an internal flow, mixture of water and air. The problem is that I keep getting negative values for minimum alpha of air and of water. I tried implementing limiters such as valLeer01 and MUSCL01 methods for div(phi,alpha) and div(phirb,alpha) but no success. I looked through the forum and found a similar post but it couldn't solve my problem. Here are the numerical schemes that I am using:

Code:

ddtSchemes

{

    default         Euler;

}



gradSchemes

{

    default cellLimited Gauss linear 0.5;

    grad(U) cellLimited Gauss linear 0.5; 

}



divSchemes

{

    div(phi,alpha)  Gauss MUSCL01;

    div(phirb,alpha) Gauss MUSCL01;



    div(rhoPhi,U)  Gauss vanLeerV;

    div(phi,p)      Gauss upwind;



    div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear;

    

    "div\(phi,(k|thermo:rho.water|thermo:rho.air|)\)"        Gauss linearUpwind default;

    "div\(rhoPhi,(T|K|epsilon|k)\)"     Gauss linearUpwind default;

}



laplacianSchemes

{

    default Gauss linear limited 1.0;

}



interpolationSchemes

{

    default         linear;

}



snGradSchemes

{

    default        limited 1.0; 

}

and here are the solver options that I am using for alphas:

Code:

    "alpha.*"

    {

        nAlphaCorr      1;

        nAlphaSubCycles 2;

        cAlpha          1;

        icAlpha         0.25;

        

        MULESCorr       yes;

        nLimiterIter    8;

        alphaApplyPrevCorr  true;



        solver          smoothSolver;

        smoother        symGaussSeidel;

        tolerance       1e-6;

        relTol          1e-3;

    }

Any suggestion is appreciated.