Influence of the electro-maonetic stirring on the boundary layer of a molten steel pool

Electro-magnetic stirrers, applied to the mold of a continuous caster, induces electromagnetic forces that influence the steel flow pattern modifying the casting parameters. The steel quality has been highly improved by the application of this magneto-hydro-dynamic (MHD) technique. Anyway, the complexity of the MHD interaction made difficult the complete comprehension of the factors that contribute to eliminate the defects due to the inclusions in the cast products. The optimization of the MHD techniques is still the object of a large research effort, which utilizes both experimental activity and numerical simulation. In this paper, the numerical simulation of the 2D flow pattern of the molten steel in a mold for billets has been done. The attention is focused on the gradient of the velocity of the molten steel near the wad and on the effects that the gradient change determines on the inclusions, which are present in the metallic pool. Actually the increase of the velocity gradient corresponds to the increase of the forces that can clean the solidifying shell from the inclusions.