Numerical simulation of collision removal of inclusion in swirling flow tundish

Abstract

Abstract The SFT (swirling flow tundish) is a kind of tundish with SC (swirl chamber) placed in the flow injection zone. The gravity potential energy of the molten steel is converted into rotation kinetic energy as entering into the tundish from the bottom of the SC along the tangential direction. The inclusions tend to collide and aggregate as following the rotating molten steel in the SC. In this work, the collision-coalescence behavior of inclusion was investigated by the mathematical simulation with PBM (population balance model) model, and the removal rate of the inclusion was investigated by the DPM model. The results show that, under the same operating conditions, the average diameter of inclusion at the outlet of the tundish increases from 4.25 μm to 4.35 μm with the introduction of the SC, which means that the SC promotes the collision and aggregation of inclusion. The inclusion removal rate of SFT is 33.09% without considering the collision-coalescence, and it increases into 43.20% as considering the collision-coalescence. The results of considering the collision-coalescence of inclusion is more consistent with the actual movement of inclusion in the tundish.