Simulation of surface roughness on the flow pattern in the casting process

In this investigation a mathematical model has been developed for simulation of the incompressible flow with free surface during mould filling. The simulation 3D melt flow with free surface is based on the SOLA-VOF technique. In the model the effects of variations parameters including heat and mass transfer as well as influences of backpressure, and friction have been considered. The solid and free boundary conditions have been modified and a new algorithm has been developed to calculate the effect of wall–slip ratio, during mold filling. In this algorithm, the effect of wall–slip ratio on the filling pattern has been modeled with an experimental function. In order to verify the computational results, a thin Al–7.5 Si% alloy plate has been poured into a sand mould with a transparent face to take into account the effect of surface roughness on flow pattern, the amount of erosion, and impact of the molten metal on the sand mould, utilizing photography. The comparison between the experimental and the simulation results of sequence filling shows a good consistency that confirms the accuracy of the model for predicting the erosion phenomenon in the moulding materials.