Water analogue validation of numerical model for fluid flow during slow shot phase in die casting process

Abstract

Air that becomes entrapped in the molten metal during the die casting process has a major effect on the formation of porosity in horizontal cold chamber die castings. In this study, a three-dimensional computational fluid dynamics model was developed to study the flow patterns of liquid metal in the injection chamber, in which the moving boundary conditions of the plunger movement was considered in detail. According to the principle of die casting machines, a water analogue system was designed and built to investigate the slow shot process. A colour high speed camera was used to record the fluid flow patterns under different plunger movement profiles. The numerical simulation results agreed well with the water analogue experimental results, which validated the numerical model of shot processing in the cold chamber of the die casting process.