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A mathematical model has been developed to analyze molten metal flow, considering the effects of argon gas injection and static magnetic-field application in the continuous casting process. The kturbulence model is used to calculate the turbulent variables. A homogeneous fluid model with variable density is employed to tackle the molten metal-argon gas flow. The electromagnetic force is incorporated into the Navier-Stokes equation, and the effects of boundary conditions of the magnetic field on the velocity distribution near the mold wall are included. A good agreement between the numerically obtained flow-field results and measurements is obtained. The argon gas injection changes the molten metal flow pattern, mainly in the upper portion of the mold. By applying the magnetic field, values of the averaged velocity field in the bulk decrease significantly, and, especially at the top free surface, they become very small, which can cause meniscus freezing. When magnetic-field application and argon gas injection are used together, the external flow field out of the gas plume is significantly suppressed; nevertheless, flotation of gas bubbles is still active and is not affected directly by the magnetic field. Although the penetrating length of the gas plume is shortened, the argon gas bubbles in molten steel still cause fluctuation at the top free surface, which prevents the occurrence of freezing.

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Euler-Euler Large Eddy Simulation (EELES) scheme has been developed to simulate the two-phase flow of argon gas and molten steel in slab continuous casting mold. The Euler-Euler approach is used to describe the equations of motion of the two-phase flow. The drag force, lift force and virtual mass force are incorporated in this model. Both turbulence of argon gas and molten steel are simulated using large eddy simulation (LES). Simulation results agree acceptably well with the water model experimental measurements of instantaneous flow structures. The flow pattern in the lower recirculation zone is expected to be asymmetrical between the left and right sides of the mold. The flow pattern is changeover; the direction of flow deviation is different from time to time. The time intervals for changeover appeared to vary randomly. The long-term asymmetry in the lower roll is due to the turbulent nature instead of the variation of other operating parameters. The turbulent flow in the mold includes multiple vortices. Those vortexes make the flow field to be more complex. Two typical transient flow structures, consisting of clockwise or counterclockwise rotational direction vortices, are found in the upper roll.