COMMUNICATIONS IN NUMERICAL METHODS IN ENGINEERING Commun. Numer. Meth. Engng 2003; 19:679–687 (DOI: 10.1002/cnm.633) High pressure die casting simulation using a Lagrangian particle method S. Kulasegaram * , J. Bonet, R. W. Lewis and M. Prot Civil and Computational Engineering Centre, School of Engineering; University of Wales Swansea; Singleton Park; Swansea SA2 8PP; U.K. SUMMARY Mould lling simulation in high pressure die casting has been an attractive area of research for many years. Several numerical methodologies have been attempted in the past to study the ow behaviour of the molten metal into the die cavities. However, many of these methods require a stationary mesh or grid which limits their ability in simulating highly dynamic and transient ows encountered in high pressure die casting processes. In recent years, the advent of meshfree methods have expanded the capabilities of numerical techniques. Hence, these methods have emerged as an attractive alternative for modelling mould lling simulation in pressure die casting processes. In the present work, a Lagrangian particle method called corrected smooth particle hydrodynamics (CSPH) is used to simulate uid ow in the high pressure die casting cavity. This paper mainly focuses on deriving the fundamental governing equations based on a variational formulation and presents a number of mould lling examples to demonstrate the capabilities of the CSPH numerical model. Copyright ? 2003 John Wiley & Sons, Ltd. KEY WORDS: meshless method; high pressure die casting; variational formulation; CSPH; SPH 1. INTRODUCTION High pressure die casting is a manufacturing process used to produce aluminium, magnesium or zinc alloy castings, often of very complex shapes that require very little additional machin- ing. During the high pressure die casting process, molten metal is poured into the shot sleeve and then injected into the die cavity by the plunger under high pressure. The die cavity ll time is extremely quick, typically 0:1s or less [1]. The gate velocities range from 40 to 60m= s but can be as high as 200 m= s [1]. The geometric complexity of the dies leads to a complex ow of molten metal, while the high speeds lead to signicant free surface fragmentation and droplet formation. In the high pressure die casting process, the experimental evaluation is very dicult because of the speeds, pressures, temperature, thin section of the die cavity and the bulk of the die. Improvements to both product quality and process productivity can be brought about through improved die design. These include developing more eective control * Correspondence to: S. Kulasegaram, Department of Mechanical Engineering, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, U.K. Received 22 March 2002 Copyright ? 2003 John Wiley & Sons, Ltd. Accepted 4 December 2002