Numerical Simulation of Inclusion Removal by Bubble Injection in the Submerged Nozzle With Swirling Flow

The removal of inclusions is of great importance in metallurgical industry. In this paper, a novel swirling flow generator (SFG) is intended to be installed around the inlet of the submerge entry nozzle (SEN) in the tundish to generate a swirling flow in the SEN by utilizing gravitational potential energy. Herein, the motion and interaction between bubbles and inclusion particles in the swirling flow field are simulated by Discrete Phase Model (DPM) in the three-phase fluid flow. In the swirling flow, collision between the inclusions particles and bubbles is governed by a self-developed User-Defined Function (UDF) program. The radial pressure gradient force causes inclusion particles to move toward the center. In the central area in the SEN, the collision rate between inclusion particles and bubbles increases significantly. Thus, bubble injection in swirling flow is beneficial to the removal of inclusion particles. The removal efficiency of inclusion particles of various sizes in tundish with SFG is investigated in this paper, which is valuable for the design of the industrial tundish.