Physical and mathematical modelling of inert gas shrouding in a tundish

Abstract

Inert gas shrouding practices in water model tundishes were mathematically simulated using the finite volume based program ANSYS 12. The fluid within the tundish and the ladle shroud was assumed to be Newtonian and incompressible (water), and the flow within the shroud was assumed to be predominantly bubbly i.e. discrete bubbles are formed, and these move down the shroud along with the down-flowing water. Thus, the numerical model was developed using the Discrete Phase Modeling (DPM) approach, along with the standard k-e turbulence model with two way turbulence coupling. Predicted flow fields, slag behaviour and bubble trajectories were investigated and then compared with experiments in the full scale and one third scale water model tundishes. Various experimental measurements compared well with predictions from the mathematical model, which was shown to slightly over-estimate depths of penetration of the bubble column by 5-15%. © 2011 ISIJ.