Fluid Flow and Heat Transfer Simulations of the Cooling System in Low Pressure Die Casting

Abstract

Low pressure die casting (LPDC) is the preferred method to manufacture cost-effective automotive wheels.Cooling systems and channels of a low pressure die casting are critical to obtain better mechanicalproperties. Both steady-state and time-dependent (transient) Computational Fluid Dynamics (CFD) analysesof the cooling channels and the die cooling system, both in conjugate and solid-only models, are performedand the pipe flow part of the results are compared with the available experimental data. Pipes operate at aschedule transiently, therefore a complex time-dependent simulation is required. The aim is to construct asimplified approach in which only the solids (die and cast wheel) are considered and pipe cooling isrepresented by heat transfer coefficient distribution obtained from the much faster steady-state simulations.Successful results are obtained by significantly reducing the computational time while retaining a similarlevel of accuracy. Finally, cooling channels with eight different diameter stream-wise distributions areanalyzed to explore their impact on pipe exit velocity and mass flow rate as a guidance towards futureworks. Wheels are cast with the simulated cooling system and are approved by mechanical tests.