This paper describes a three-dimensional numerical model that is used to predict the transient thermal behavior of the metal injection system of a hot chamber pressure die casting machine. The behavior of the injection system is considered in conjunction with the of the die. The Boundary Element Method (BEM) is used to model the transient thermal behavior of the injection system elements and the die blocks. A perturbation approach is adopted. By adopting this approach, only those surfaces over which a significant transient variation in temperature occurs need be considered. The model assumes that a corresponding steady-sate analysis has first been performed so that time-averred thermal information is available. A finite element based technique is used to model the phase change of he liquid metal in the die cavity and in the injection system. At injection the nozzle and die are assumed to be instantly filled with liquid metal, however, a procedure is presented that attempts to model the heat transfer associated with the flow through the nozzle, gate, and runner regions during injection. Model predictions are compared against thermocouple readings and thermal images obtained from experimental tests. Good agreement is obtained between predicted and measured temperatures. The tangent thermal behavior of an existing hot chamber injection system is investigated in detail and recommendations for improved performance are made. IN an attempt to improve the solidification pattern of he casting and the thermal behavior of the injection system, a redesign of he experimental die is con
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