Simulation of Casting Geometry Effect in Low-Frequency Electromagnetic Casting

Abstract

The purpose of this paper is to perform the simulations of the low-frequency electromagnetic casting for various geometries and analyze the results. The casting model includes a coupled set of mass, momentum, energy, and species conservation equations. Lorentz force is computed with the induction equation and used in the solidification model. The coupled physical model is solved in cylindrical coordinate system and can be used to model aluminum alloy billet production. Explicit scheme is used for the temporal discretization, while the meshless diffuse approximate method is used for the spatial discretization. The method is localized with subdomains containing 14 local nodes. The Gaussian weight is used in the weighted least squares minimization. Furthermore, the Gaussian is shifted upstream, when an upwind effect is required in order to increase the convection stability. Direct chill casting under the influence of electromagnetic field (EMF) is simulated for various inflow geometries. The material properties of Al-5.25 wt%Cu are used. The casting parameters and material properties are constant in all presented simulations, while EMF is turned off in some cases in order to study its effect on solidification. The results show that EMF has a great effect on the melt-flow and solidification. Oscillatory, instead of a steady-state, solution is obtained in case of certain geometries in EMF casting. The effect of geometry is hard to quantify, which shows the need for implementation of the realistic inflow geometries in casting simulations.