No Laplace Pressure (interface curvature) in multiphase level set simulation

Hello everybody,
I am simulating in version 4.3 a drop of oil in water with the level set multiphase module coupled with the electrostatic module as in the electrocoalescence example from the model library.
The difference in my model is that I am applying a periodic flow condition to simulate an infinite channel and my bubble is actually occupying all the transverse dimension of the channel (cloggin it), therefore touching the walls.
As a result, the two bubble interfaces become straight lines and don't show any curvature due to the Laplace pressure as they should.
I am imposing a wetting angle as a boundary condition, but even without the shape of the bubble turns from the curved one I assign originally to a straight line. I understood that the level set method implements already by himself the laplace pressure by using the gradient of the level set function.
The result is independent of the quality of the mesh.
Maybe I am missing something in my model setup, I would extremely appreciate any insight or help !
Thank you a lot ,

Stefano Facchin

i'll post soon an image and the model.