Optimization and continuous casting: Part II. Application to industrial casters

Abstract

The optimization of the operation and design of continuous casters is formulated and solved using a nonlinear programing (NLP) strategy. Using objective and constraint functions that relate to casting performance and steel quality, the optimization is performed using a successive quadratic programming (SQP) algorithm applied to a heat flow model. Theoretical development for this approach was presented in Part I of this study.[2] In this article, we present the results of this approach for 12 casting cases. Here, billet and slab caster models were considered for rate maximization, rate minimization, and maximization of enthalpy at the.cutoff point. Both of these are two-dimensional heat flow models based on industrial continuous casters. The results show that optimization is a viable and effective tool for developing operating strategies for casters. Moreover, many of the optimal solutions are not likely to be discovered through normal operating practice or case study. For example, spray heat-transfer coefficients need not be in decreasing order, and the maximum casting rate may be slightly different from the case for maximum enthalpy in the strand.