THE EFFECT OF TURBULENCE ON SOLIDIFICATION OF A BINARY METAL ALLOY WITH ELECTROMAGNETIC STIRRING

Electromagnetic induction is considered as a means of altering convection during the solidification of a Pb-19 wt pct Sn alloy. Application of a time-varying magnetic field induces Lorentz forces, which augment thermal buoyancy forces in the melt and oppose solutal buoyancy forces in the mushy zone. A continuum model for binary solid-liquid phase change is extended to account for turbulence, and laminar and turbulent flow predictions are contrasted. Results indicate that turbulence decreases the propensity for channel development and macrosegregation by enhancing mixing and reducing the effective Lewis number from 8600 to near unity.