Introduction

Metallurgical aggregates are characterised by the interaction of several phases. Especially within secondary metallurgy vessels like ladles or converters comprises the liquid steel phase, the buoyant liquid slag phase, a gas phase for purging/stirring/processing, and the atmosphere atop. A similar character can also be found within the continuous casting (CC) process where in the submerged entry nozzle (SEN) gas is injected into the liquid steel. This mixture is directed into the mould which comprises the interfaces of steel-slag as well as slag-atmosphere. Furthermore, the interaction of the liquid steel flow field with magnetic fields is used to manipulate the flow to a favourable state.

Within this project the main phase of interest is represented by the liquid steel and its interactions with different phases or external magnetic fields. From a modelling point of view the interfaces of multiphase systems might be tracked by Volume of Fluid (VoF) approaches which are capable to resolve different phases based on the density ratio within the grid cells. Already this point unveils problems since the grid cells of industrial applications need to be quite coarse to achieve reasonable computational times. The requirement of sharp interfaces (e.g. to resolve small bubbles) and especially high injection gas rates need to be further investigated to include all necessary interactions like multiphase-turbulence, interfacial tension gradient triggered convective flows, etc. Moreover, the approach to not resolve the small structures but convert/map them to Lagrangian particles (and vice versa if coalescence increases their size) will be investigated to design a suitable model. Since the common models often neglect or drastically simplify effects which are observed within high temperature flows this project targets the development of applicable and suitable models for the steel industry.