valueFraction change with time for multiphase simulations
 

Hi people ;

i have a multiphase simulation of water drop on a flat plate with partial slip .

so the plate boundary should be wall with a given valueFraction

i want the partial slip affect the water only not the air (partial slip on water drop and no slip on the air)

i can put a nonuniform boundary condition for the drop seat for alpha_1 with a valueFraction i want. and for air = 1 (which corresponding to no-slip condition)

the problem here is that the drop should move :) so that the valueFraction should change with alpha_1 change on the wall

could any one have any experience in openFoam with such simulation

i want the valueFraction be associated with water phase only when the time change . is that available in OF?

thank you.

Hello, I know this is an old thread. Now I have this problem too. How did you solve it? Thank you in advance~

There is no boundary condition for such problem out of the box. However, you can use a codedFixed boundary to program it yourself. For that purpose, you need to get the face values of alpha and check wheater you have alpha equal zero, then apply a velocity vector if zero zero zero. If it is one, apply what ever you want to do with the water, and inbetween you have both phases. Shere you can make a blending function or what ever you think is correct.

Hi,Tobi

Thank you very much for your advice! I want to implement a BC morified by partialSlip. In partialSlip BC, a const valueFraction is read, and I want to set valueFraction change with the alpah of two phase flow. But I'm a beginner of OpenFoam programming, could you tell me more details or give a similar example about it? Thank you in advance.

#
<patchName>
{
type partialSlip;
valueFraction uniform 0.1;
}
#