Abstract: Based on the similarity theory, a 1∶3 water model experiment system was established to study the influence of different submerged nozzle (SEN) structures on slag entrapment behavior in a continuous casting mold with argon blowing. The variation of liquid level fluctuation and argon bubble distribution under different nozzle structures were investigated. The results showed that the main ways of slag entrapment in the mold were bubble impacting slag entrapment, shearing slag entrapment and emulsion pumping slag entrapment. When the concave bottom nozzle was used, it was easy to produce bubble impacting slag entrapment and emulsion pumping slag entrapment. When the convex bottom nozzle was used, it was easy to produce shearing slag entrapment and bubble impacting slag entrapment. When the concave bottom, rectangle, 20° inclined nozzle was used, the minimum number of slag entrapment was observed, that was 4 times/min. The liquid level fluctuation of convex bottom nozzle was more severe, and the rectangular nozzle was not conducive to reduce the liquid level fluctuation. The maximum wave height could reach 2.5 mm at the quarter position of the width of the mold at the 20°inclination angle convex bottom nozzle. The bubble distribution was more dispersed and the impact depth was greater in the large angle nozzle. The movement distance of argon bubble with liquid steel was longer with convex bottom nozzle.

Key words: continuous casting mold, structure of SEN, level fluctuation, slag entrapment, water model experiment