Boundary condition issue in multi-phase model
 

Hi,

I am new to CFX, but have used Flow-3D and Magma previously.

I have a simple 2 phase, heterogeneous (air and fluid) casting model. The mold is initially full of air, fluid enters the domain through a pressure inlet boundary. I have specified 3 faces of the mold as boundaries of 'opening' type, with the fluid volume fractions 1 and 0 for air and fluid respectively (under fluid values tab). I expected this to allow the air out of the domain but not the fluid. This is my aim.

However, upon running the simulation both air and fluid are leaving the domain through these three boundaries.

My question is, in CFX how do i specify a boundary which will vent the air from my model, but not allow the fluid to leave the domain?

I'm sure that there is a simple answer to this but I'm not finding it.

Any help would be much appreciated.


Carl