Numerical Investigations of Stirring Induced Flow On Solidification and Interface Behaviour in Continuous Casting Mold with Bifurcated Nozzle

Abstract

Electromagnetic stirring(EMS) is a technique that has the potential to improve steel quality with fine microstructure by fragmentation of dendrites and enhancing the inclusion removal. The success of implementing the EMS lies in the selection of key input parameters such as position, frequency and current density of the stirrer. In the present study, an integrated mathematical model consisting of liquid steel solidification and two phase interface is numerically developed with the use of EMS. The enthalpy porosity and volume of fluid(VOF) model are adopted for numerical modelling analysis of solidification and interface level fluctuation respectively. The results reveal that on moving EMS downwards decreases the maximum magnetic field value, widens the mushy zone and promotes the stability of the interface. Current intensity and frequency are seen to have the opposite effect on stirring intensity and interface fluctuation. With an increase in frequency, both stirring intensity and interface level fluctuations decrease while the high liquid fraction region increases. Moreover, current density enhances the swirling flow intensity and homogenizes the liquid fraction, thereby promoting equiaxed grain formation. Interface fluctuation is seen to increase with current density.