[csh4206]

I am setting up a VOF simulation of an open channel flow problem, and have defined two regions: water and air (both are rectangular). At the inlet, I am using velocity inlet and setting the relative concentrations (100% H20 for water region; 100% air for air region), and pressure outlet for both. I am using a flat VOF wave and defined the necessary water and air velocities, density and the H2O surface elevation at the inlet.

What type of boundary should I use for the air-water interface along the length of the channel for my boundary condition? This corresponds to the flat water surface air-water interface at the beginning of the simulation, however, the free surface will change and develop small waves during the course of the simulation because of a surface-piercing cylinder.

Thanks in advance for any input.

[ping]

you don't need two region for this so just have one region - do the vof tutorials to understand how

you can complicate the model with additional regions and the interface will be an inplace one to all flow of both air and water depending on where the free surface is