Analysis of macrosegregation during slab continuous casting using 3D-longitudinal 2D hybrid model

ABSTRACT To improve the computational efficiency of simulating the macrosegregation process that occurs during continuous casting of steel slabs, a new hybrid method combining three-dimensional and longitudinal two-dimensional models was developed to consider the turbulent flow, heat transfer, solidification, and solute transport phenomena. The reasonability of the performed computational domain division was determined, and the model accuracy was verified experimentally. Using this approach, the solute distribution characteristics and central segregation during continuous casting were examined in detail. The obtained results revealed that recirculation flows in the turbulent flow region play a critical role in the distribution of solute elements near the slab surface. Owing to the redistribution of solute elements at the solid–liquid interface and the movement of the solid–liquid interface towards the slab centre during continuous casting, the solute elements in the slab centre are continuously enriched, ultimately resulting in central segregation.