Numerical Simulation of Macrosegregation Behavior of Billet During Continuous Casting

Abstract

The three-dimensional numerical model, which coupled turbulent flow, solute transport, and heat transfer, was developed to investigate the macrosegregation behavior of high carbon steel billet in the process of continuous casting. The outlet of the model was located where at the end point of solidification to study the distribution of solute element in entire billet. The momentum equation, energy equation, and component transfer equation in multicomponent system were solved by ANSYS Fluent software. The influence of double diffusion convection on flow field was taken into account in current work. Furthermore, the accuracy of the model was verified by experiment. The results indicate the turbulent flow plays an important role in the distribution of solute elements of initial solidified shell in the mold. The suction effect which is at the final stage of solidification aggravated the central segregation of billet. The redistribution of solute at the solid–liquid interface leads to the higher C concentration at the solidification front. At the end of solidification, the maximum positive segregation occurs at the center of billet, while the minimum negative segregation emerges at 9 mm from the surface of billet. The corresponding segregation degrees of C for them are 1.71 and 0.75, respectively.