Effect of Casting Speed on Multiphase Flow and Slag Entrainment Caused by a Triple‐Port Submerged Entry Nozzle

Abstract

In this study, a transient three‐dimensional numerical model is developed. The model employs large eddy simulation (LES) to resolve unsteady turbulent flows, the Smagorinsky–Lilly model to resolve sub‐grid scale structures, and the volume of fluid (VOF) method to track the motion of three continuous phases (air, slag, and steel). Based on surface integral and numerical simulation, a new method is proposed to calculate fluid flow rate at each port. Three distinct flow regimes of a steel jet are identified and characterized: the initial jet region, the main jet region, and the impingement region. The flow distribution exhibits a consistent pattern, with approximately 26% of the flow passing through the bottom port and 74% through the side ports under the given SEN structure. The flow rates through the two side ports are nearly equal. Although the casting speed does not affect the flow rate percentages, it does influence the absolute flow rates. A dimensionless Sa value is proposed to evaluate slag entrainment in steel, and this value is successfully established to evaluate its effectiveness at both detecting slag entrainment and evaluating its severity. This work is expected to improve control of slag entrainment in continuous casting processes.