Interfacial Heat Flux Estimation in a Funnel-Shaped Mould and Analysis of Solidification Characteristics in Thin Slab Continuous Casting

Abstract

An inverse heat transfer model based on Salp Swarm optimization algorithm is developed for prediction of heat flux at the hot faces of a mold in thin slab continuous casting. The industrial mold considered in this work is a funnel-shaped mold having complex arrangement of cooling slots and holes. Significant variations of heat flux along the casting direction, as well as across the width are observed. Subsequently, the obtained heat flux profile estimated by the inverse method is used to analyze the fluid flow and thermal characteristics of the solidifying steel strand inside the mold. Three different recirculatory zones are present due to molten steel flow, affecting the thermal and solidification characteristics significantly. The effect of these recirculatory flows on remelting phenomenon, and consequent formation of thinner shell at the mold outlet leading to quality control issues in the casting process have been discussed. Another practical issue of depression in the wide face shell thickness at the mold outlet has been identified, and its cause has been related to the location of the submerged entry nozzle and the high speed of the molten steel inflow.