Numerical simulation of macrosegregation formation in large round bloom continuous casting
The three-dimensional coupled model was developed to consider the turbulent flow,heat transfer,solidification,and solute transport phenomena during the vertical continuous casting forΦ785 mm large round bloom.By using the model,the distribution of solute elements in the bloom from meniscus to full solidification was predicted,and the formation process of macrosegregation in the large round bloom continuous casting was examined in detail.The simulation results show that the"solute washing effect"of molten steel on the solidification front at the early stage of continuous casting is the main reason for obvious negative segregation band in round surface region.With the continuous solidification of molten steel,the solute elements of residual melt in the round center are continuously enriched,resulting in the formation of center segregation.The central maximum positive segregation index of C is 1.08.In addition,the severity of macrosegregation for different solute elements is different,however the distribution for different elements exhibits the same tendency.
large round bloomflow fieldsolidificationmacrosegregationnumerical simulation