Regarding mold filling simulation in Fluent

Nitin Pathak

I m trying mold filling using VOF model. The basic set is like this. In model we have sprue through which the liquid metal (say Al) is poured with some velocity. It is basically bottom feeding and the final mold cavity that is to be filled is rectangula plate. I m giving the face of sprue as the velocity inlet with some velocity and the VOF 1 for phase-2 (i.e. Al phase). All the other boundaries are wall conditions. but the mold filling is taking too much time when i compare with the givn results. because i m assuming all the walls so the is no way to escape the air nd probably due to pressure build up the rate of mold filling is suppressed. when i apply either pressure-outlet/ outlflow boundary condition, it results into splashes of metal flow. what boundary condition should give to the upper face of mold so that air can escape. thanks.