Numerical investigation of bubble behavior and multiphase flow in ladle using purging plug with inclined slit designs

Inclined slits are introduced in purging plugs to improve fluid flow characteristics and control bubble behavior. In this study, the discrete phase model was used to describe bubble behavior, and a file acting as a user-defined function was compiled to define the location and inclined angle of the injected bubble, the flow rate, and the initial bubble diameter. Because of the variable density and pressure in a high-temperature melt, bubble expansion considerably affects the behavior of bubbles, which was considered in our numerical simulation. The results showed that the divergent slit reduces the collision probability of generated bubbles as they rise, decreasing the average size of bubbles in the ladle. Moreover, the converging slit intensified the turbulent kinetic energy dissipation caused by bubble collisions. It is essential to improve the flow characteristics of molten steel and control bubble size by varying the inclined slit angles of the purging plug in a ladle, which is also applicable to gas stirring reactors with a multi-hole nozzle.