Shape Optimization of Runners for Die Casting to Reduce Air Entrainment in Flow Paths

Abstract

  This study aimed to optimize the design of a runner for high-pressure die casting using computational fluid dynamics (CFD) simulations. A runner is a part of the flow path through which molten metal enters a product part. As a design challenge, we sought to optimize the shape of the runner to minimize air entrainment in the runner and to align the flow of molten metal after passing through the runner. The problem was solved using our proposed shape optimization method. The method is based on a genetic algorithm (GA), and can directly treat a geometric shape that is comprised of several curves as an individual of the GA in the form of a set of mathematical functions. The effectiveness of the optimized shape of the runner was eventually demonstrated with water-model experiments using a visualization device for die casting.