[Mat_fr]

Hi everybody,

I'm doing a VOF simulation with Fluent and here's my problem :

The volume fraction is a variable equal to 1 in the primary phase and 0 in the secondary phase. When the value is between 0 and 1, the cell is crossed by the interface. An approximation of the interface position is thus obtained with alpha = 0.5.
Right ?

In my domain, I have volume fractions from 0 to 0.4, with very large area of non-zero volume fraction. What does it means ?
I can understand that the interface could be a bit diffuse, but not so much. And in addition the volume fraction does not go above 0.5 ? Where is the interface thus ? Are these results reliable ?
In fact, it looks like a Euler-Euler simulation.
(The continuity and momentum residuals are ok.)

Thanks for your help !

Best,

Mat

[oj.bulmer]

Few images will help. But yes, VOF is typically used to resolve the interfaces between two fluids distinctly separated, unlike Euler models which work with typically dispersed fluids.

OJ

[Mat_fr]

Thank you for your answer !

At the moment, I'm not sure if I can show the geometry, sorry.
But my question is simple : If the volume fraction does not reach 0.5, does it means that Fluent is not able to capture the interface and thus also that the computation is non-realistic ?

Best,

Mat