Novel inverse heat transfer methodology for estimation of unknown interfacial heat flux of a continuous casting mould: A complete three-dimensional thermal analysis of an industrial slab mould

Abstract

Accurate quantification of interfacial heat flux between the continuous casting mould and slab/billet is essential for the design and development of the products as well as operation and quality control of the casting process. Apart from empirical correlations, inverse heat transfer methods are typically employed to predict the heat flux variation by assuming a one-dimensional variation of heat flux along the casting direction. The assumption of one-dimensional heat flux often leads to significant error especially in determining the corner heat flux which affects the shrinkage behaviour and thereby, the quality of the products of casting. Previous studies have recognized this error and assumed this error of heat flux as a constant deviation to account for the longitudinal and transverse variation of heat flux. In this work, a novel methodology has been presented to predict the variable interfacial heat flux of a three-dimensional mould domain by estimating the parameters of a characteristic heat flux profile using an inverse heat transfer technique based on Salp Swarm Algorithm (SSA). This methodology uses limited experimental data or on-site plant recorded data. Representative cases of billet and slab moulds have been considered based on the available plant data. Results indicate that the mould corner heat flux is considerably different from that of the typically assumed value of 67% of the centre heat flux as reported in the literature with deviation reaching as high as 56% near the meniscus for a slab casting mould. The proposed methodology is simple to implement and is recommended for studies aimed towards realistic estimation of unknown boundary heat flux in a continuous casting process.