Liquid film
 

I have problems getting a solution for my 2D liquid film-gas flow. The channel height is 2cm and the initial film thickness (second inlet boundary) is only 0.3 mm. There is a high velocity difference, where the gas velocity is about 33 m/s and the film velocity is about 2-3 m/s. Does anyone have a suggestion to how I should create the mash node spacing for the two inlets?