Numerical investigation of in-mold electromagnetic stirring process for fluid flow and solidification

Abstract

Purpose The purpose of present investigation is to analyze the in-mold electromagnetic stirring (M-EMS) process and the effect of stirrer frequency on fluid flow and solidification in a continuous casting billet caster mold. Design/methodology/approach A hybrid approach involving finite element and finite volume method has been used for the study. Finite element model is used to calculate time variable magnetic field, which is further coupled with fluid flow and solidification equations for magneto-hydrodynamic analysis with finite volume model. Findings Results show that though superheat given to steel before its entry into the mold is quickly removed, solid shell formation is delayed by the use of M-EMS. Final solid shell thickness, however, is slightly reduced. Increase in frequency is found to increase the magnetic flux density and tangential velocity of liquid steel and decrease in diameter of liquid core. Practical implications The work is of great industrial relevance. The model may be used to design industrial setup of in-mold electromagnetic stirrer and process could be analyzed and optimized numerically. Originality/value The paper evaluates the influence of M-EMS and its frequency on solidification and flow behavior in the continuous casting mold. The iso-surface temperatures from pouring temperature to liquidus temperature inside the mold have been shown. The findings may be useful for the steelmakers to reduce the defect in continuous casting.

Influence of M-EMS on Fluid Flow and Initial Solidification in Slab Continuous Casting

“…Wang et al [15] developed a 3-D coupled model considering electromagnetic field, flow field, heat transfer and level fluctuation under different EMS positions in continuous billet mold, and found that the velocity and wave height at steel/slag interface decreases under lower stirrer position. Maurya et al [16][17][18] analyzed the influence of EMS on flow and solidified shell under different EMS currents and frequencies. However, little research considered the influence of EMS on the flow and initial solidification on slab.…”

Effect of Mold Electromagnetic Stirring on Metallurgical Behavior in Ultrahigh Speed Continuous Casting Billet Mold

“…Maurya et al [17][18][19] investigated the effect of the stirrer width at different currents and frequencies and the stirrer position on the fluid flow and solidification behaviors in a mold using M-EMS. Fang et al [20] and Wang et al [21] developed multiphysical models to predict the effect of the stirrer position on the magnetic field distribution, fluid flow streamlines, temperature distribution, inclusion removal, solute diffusion, mold-level fluctuation, and slag entrapment behavior.…”

Electromagnetic Stirring and Joule Heating in Continuous Casting Mold

“…To account for the impact of the magnetic field on the fluid flow, Lorentz force derived in Equation ( 6) has been added to the standard Navier-Stokes equation, as shown in equation (13). Because of the decreased porosity during solidification, the mushy zone's momentum decreases.…”

“…Equations ( 15) and ( 16), which indicate the solutions for the governing differential equations for turbulent kinetic energy (k) and dissipation rate ( ), respectively: To verify the correctness of the model, they have been validated individually for the magnetic field and solidification model. The detailed validation has been reported by Maurya and Jha [13]. A comparison of fluid flow with and without M-EMS has been done in order to investigate the EMS process.…”