Modelling oscillation mark formation and slag infiltration through the coupling of multiple physical phenomena during continuous casting

Continuous casting involves a number of phenomena which have considerable impact on process efficiency and product quality. These phenomena include metal flow dynamics, heat transfer, slag infiltration and shell solidification. A multiphase model is presented to study the complex interactions between these processes occurring simultaneously within the mould. Using a multiphase model and extremely fine meshes in the meniscus region (minimum cell size ∼100 μm), allows direct simulation of slag infiltration into the shell-mould gap without applying common simplifying assumptions such as the Bikerman equation. It also allows direct calculation of the heat transfer through the mould, slag and shell avoiding semi-empirical thermal-resistance models. The ultimate aim is to determine the influence of the metal-slag flow on shell solidification and lubrication behaviour within the mould. Slag infiltration and oscillation mark formation were successfully tracked through this approach and new insights into their triggering mechanisms are given. Accurate modelling of these defects would allow optimization of casting conditions in order to reduce the occurrence of oscillation marks, which are detrimental to slab quality.