Introduction
Subsequent to the operations of secondary metallurgy the liquid steel is casted into a strand (slab) by the continuous casting (CC) process. This procedure includes a reservoir vessel (tundish) for continuous feeding of the mould. The mould is supplied with liquid steel via a submerged entry nozzle (SEN) to avoid splashing and generate a beneficial flow field within the mould. Due to increasing demands on the product quality even stricter analyses and process control procedures are required. Experiences of the industrial partners unveiled that impurities can origin from these last steps of the liquid steel and subsequently trigger operational irregularities. This project is dedicated to investigate these process steps and develop numerical approaches to depict the industrial applications and the influence of different operational attritions. Since aside the numerical challenges (like turbulence modelling of multiphase systems, accretion physics of the SEN, etc) also the appearing boundary conditions are essential for a meaningful representation of the systems.
Consequently, dedicated work will be conducted to cover the industrial circumstances and materials and permit a reliable mapping and analyses of the industrial processes.
The involved processes of the CC method represent an interplay of complex physical aspects. The multiphase nature (slag, liquid steel, refractory, non metallic inclusions, and gas), the interaction of turbulence, thermodynamic character of the involved materials, and the huge bandwidth of spatial and temporal scales are the most challenging characteristics of the systems. For each subsystem (like tundish, SEN, mould) dedicated numerical approaches are developed/enhanced/used to fit best the respective needs. Aside the numerical reproduction of the involved physics a usual problem is the application of the (often with water experiments validated) models to the industrial conditions since material parameters and most of all their thermo-kinetic characteristics are not known in detail. As these parameters represents a prerequisite for the numerical investigations several serious simplifications might usually be made. To overcome these shortcomings this project includes a WP to handle these aspects and supply the numerical research with sound industrial boundary conditions.
Results and application
The combination of numerical developments with experimental and industrial boundary conditions is supposed to offer insight into a highly detailed representation of the processes at industrial conditions. Since the in-use processes are degrading with operational time also the effects of SEN accretion (clogging) and its influence on the process conditions like the mould flow field will be investigated. The overall target is to acquire a better understanding of the complex interplay of involved physical effects as well as providing an approach to simulate industrial relevant problems.