Mathematical modelling of fluid flow, heat transfer and solidification in a strip continuous casting process

Abstract

A mathematical model has been developed for prediction of the solidification front in the continuous strip casting process, through the fully coupled analysis of fluid flow and heat transfer of a solidifying shell. Fluid flow and heat transfer at the interface of the strip and mould were analysed with two- and three-dimensional (2D and 3D) finite volume methods. The numerical model considers a generalised set of mass, momentum and heat equations that is valid for the solid, liquid and solidification interval. A k–ϵ turbulence model, produced with the commercial program CFX, is used to analyse the solidification process of Cu–Cr alloy in the mould region of the caster. The heat flow and solidification processes have been studied experimentally. Cooling curves during solidification were registered using a thermocouple of type K connected to a data acquisition system. Temperature measurements were also performed in the mould and cooling water. The measured heat flux profiles were used as boundary conditions for the mathematical model. The fluid flow, temperature and heat flux distributions in the mould region of the caster were computed. The shape and location of the solidification front were also determined. Through the iterative analysis of the fluid flow, heat transfer and solidification behaviour, the heat transfer coefficient between the strand and the mould has been determined. The predicted temperature and heat flux distributions were compared with experimental measurements and reasonable agreement was obtained.