Smearing of volume fraction in contact line
 

Dear All,


I am using VOF method with a phase change model using MULES in OpenFOAM.


MULES::explicitSolve(geometricOneField(), alpha1, phi, phiAlpha, alphaSourceSp, alphaSourceSu, 1, 0);
Source terms :
alphaSourceSu = fvc::div(phi)*alpha1;
alphaSourceSp = fvc::div(phi)*0.0;


On the contact line I use contact angle boundary condition


type constantAlphaContactAngle;
gradient uniform 0;
limit zeroGradient;
theta0 40;
value uniform 0;


But there is a problem of smearing in the contact line at an increasing rate with time as seen in the attachment. Is it usual to experience in MULES scheme or can it be due to another problem which can be related to setting of contact angle boundary condition?


Thanks in advance,
Best Regards,