Pouring of liquid aluminium is typically accompanied by disturbance of the free surface. During these disturbances, the free surface oxide

films can be entrained in the bulk of liquid, also pockets of air can be accidentally trapped in this oxide films. The resultant scattering of

porosity in castings seems nearly always to originate from the pockets of entrained air in oxide films. Latest version of ProCast software

allows to identify the amount of oxides formed at the free surface and where they are most likely to end-up in casts. During a filling

calculation, ProCast can calculate different indicators which allow to better quantify the filling pattern. The fluid front tracking indicator “

Free surface time exposure” has the units [cm2*s]. At each point of the free surface, the free surface area is multiplied by the time. This

value is cumulated with the value of the previous timestep. In addition, this value is transported with the free surface and with the fluid

flow.Experiments to validate this new functions were executed.