Flow and Solidification in Billet Continuous Casting Machine with Dual Electromagnetic Stirrings of Mold and the Final Solidification

Abstract

A 3D numerical model coupling the electromagnetic field, fluid flow, heat transfer and solidification phenomena was developed to simulate the 160 mm × 160 mm billet continuous casting process of SWRT82B steel with dual electromagnetic stirrings of mold and the final solidification. The columnar region was treated as a porous zone and a generalized approach was used to calculate permeability, while for the equiaxed zone, a variable apparent viscosity model was applied to simulate the fluid flow at the initial growing stage of equiaxed dendrite. The model was validated by the measured data of magnetic induction intensity in the stirrer center and strand surface temperature. The results show that it is indispensable to consider the solidification phenomenon in the mold zone with EMS, as the fluid flow mechanism near the meniscus is quite different. With the current intensity of M‐EMS and F‐EMS increasing, the tangential velocity of molten steel rises and the central temperature decreases. As the F‐EMS is applied, the nature convection mechanism is destroyed and the temperature is promoted to distribute evenly in the mushy zone. Moreover, the results show that the coherent solid fraction has a significant effect on the temperature distribution and the fluid flow in F‐EMS zone.