Estudo do comportamento termomecânico das placas de cobre em um molde de lingotamento contínuo de placas

Abstract

One of the main quality challenges in continuous casting is associated with the proper heat transfer from the steel to the mold. This thermal exchange is influenced by various factors, such as the hot face temperature of copper plates and the contact between mold and strand. Given the difficulties in directly measuring the mold, primarily due to the inaccessibility of the areas of interest, numerical simulation has become a crucial tool to comprehend the various phenomena involved. Thus, this study aims to analyze temperature and elastic deformation in a continuous casting mold during operation through the development of a mathematical model. Using the ANSYS® 19.1 software package, a three-dimensional mathematical model to simulate the thermal and mechanical behavior of the mold was developed. Cooling water was also modeled, enabling the creation of a coupled model for heat transfer between the mold and the water. Simulations were based on boundary conditions derived from data collected during mold operation and were validated through comparisons with experimental data and information available in the literature. The highest temperature values occurred slightly below the meniscus, reaching 237.3 °C on the wide face, where there is a column with holes to fix the plate, and 277.6 °C on the narrow face, near the plate corner. Water temperature profiles showed no possibility of nucleate boiling in the channels under the studied conditions. Mold elastic deformations were predominantly caused by high thermal gradients in the copper plates. Deformation analyses revealed a tendency for the plates to bend towards the strand, especially in the center, with a maximum displacement of 0.31 mm on the narrow face. The lateral displacement of the narrow plate towards the wide plate, with a maximum value of 0.27 mm, caused local deformation in the latter, altering the contact at the interface between them, creating an increasing gap from the meniscus with a maximum value of 0.22 mm at the top of the mold.