Defining Regions and Patching
 

I am attempting to simulate laminar two-phase flow in a triangular capillary using the computational fluid dynamics code of FLUENT --- it is intended to be an immiscible flow in which the wetting phase displaces the non-wetting phase in a piston-like transport process.

According to observations, the meniscus is supposed to be a cup-like (spherical) interface separating the two phases. The problem I have is that I do not see the two phases whenever I define regions and patch them; I only see one phase in the entire length of the capillary.

I will appreciate every good suggestions.

Note: It is a microscale VOF type flow!

if you defined the 2 regions, then you go to initialize, and after (in this order) you set the vof-region with patch.