Numerical Simulation of Continuous Steel Casting Regarding the Enhancement of the Cleanliness of Molten Steel

AbstractResearch results of this chapter show a great potential to improve inclusion removal from steel melts using active and reactive exchangeable filtration systems in steelmaking. This contribution investigates numerically the performance and the efficiency of the reactive cleaning and active filtration in continuous casting tundishes. For this purpose, a Euler–Lagrange model of the disperse two-phase flow of steel melt and non-metallic inclusions has been developed. Here, implicit large eddy simulations have been employed to resolve the large-scale turbulent structures in the tundish flows. By means of multiphase flow simulations, two prototype tundish configurations (laboratory one-strand tundish, industrial-scale two-strand tundish) were researched with alumina-coated, carbon-bonded ceramic foam hybrid filters. The research aimed the investigation of the effect of the filtration system, e.g. filter position, filter shapes and filter size on inclusion removal. The results of the numerical simulations indicated the high cleaning efficiencies obtained by using a reactive filter system, where reactively generated carbon monoxide bubbles carried a high amount of inclusions to the slag. Moreover, it was concluded from the results that the contribution of active filtration to inclusion removal by the deposition of inclusions on filter surfaces was neglectable compared to the contributions of reactive cleaning.