NUMERICAL-ANALYSIS OF EFFECT OF ELECTROMAGNETIC STIRRING ON SOLIDIFICATION PHENOMENA IN CONTINUOUS-CASTING

A three-dimensional numerical analysis was carried out for turbulent f luid flow of steel in continuous casting. Recirculatory flow appears a t the top of the casting strand due to both a buoyancy force and elect romagnetic stirring. The electromagnetic forces were calculated by sol ving the magnetic induction equation with the aid of the boundary rene wal method. As a result, an increase of the equiaxed zone ratio by ele ctromagnetic stirring was predicted for constant casting speed and tun dish superheat. The increase of the equiaxed zone ratio was thought to be due to the increase of turbulent kinetic energy in the vicinity of the solid shell. The optimum condition for the equiaxed zone ratio in this study was predicted as a stirring intensity of 1400 A Hz(1/2). T he turbulent kinetic energy near the solid shell increased as the stir ring intensity increased to 1400 A Hz(1/2); hence, the equiaxed zone r atio was considered to increase with the stirring intensity. Above a s tirring intensity of 1400 A Hz(1/2) the turbulent kinetic energy did n ot increase any further, which coincided with the case of the equiaxed zone ratio in field operations.