Online Modelling of Heat Transfer, Solidification and Microstructure in Continuous Casting of Steel

S Louhenkilpi,R Vesanen,J Moilanen,J Miettinen,I Rentola,A Jokilaakso,J Laine,E-P Heikkinen,V-V Visuri

doi:10.1088/1757-899x/529/1/012051

Abstract

Advanced numerical simulation models for continuous casting of steel were developed in Finland by Casim Consulting and Aalto University in cooperation with the University of Oulu and the steel industry. The aim was to develop models that are scientifically rigorous, but also computationally fast enough to be used in online applications. The models developed are a transient three-dimensional heat transfer model, CastManager, and a solidification and microstructure model, IDS. The computing time of these models are short, and they are integrated together in one online concept. This concept is installed in the automation systems of four slab casters in Finland. Testing and validation work is in progress. The system simulates the important heat transfer, solidification and microstructural phenomena in continuous casting online. The future aim is that this information will be used for online quality control and for optimizing the process conditions to avoid formation of defects. Many quality indices have already been developed. A steady state version of the CastManager tool has also been developed, called Tempsimu.

Highlights

Computational simulation and modelling of different phenomena in casting have greatly helped to solve practical problems in industrial casters and to improve process practices and control
Advanced numerical simulation models for continuous casting of steel were developed in Finland by Casim Consulting and Aalto University in cooperation with the University of Oulu and the steel industry
For this purpose, advanced numerical simulation models for continuous steel casting were developed in Finland by Casim Consulting and Aalto University in cooperation with the University of Oulu and the steel industry

Summary

Introduction

Computational simulation and modelling of different phenomena in casting have greatly helped to solve practical problems in industrial casters and to improve process practices and control. Equation (6) is used as the boundary condition for the hotter side of the mold model, where hgap is the same gap heat transfer coefficient as for the strand model, but Text is the temperature of the strand surface, which is calculated by the strand model. IDS includes default equations for calculating the dendrite arm spacing and the austenite grain size, as a function of the composition and cooling rate, but the user can use own values too. The system simulates heat transfer, solidification and microstructural phenomena in continuous casting and the aim is to use it for quality prediction and for optimizing the casting conditions. During the casting process, CastManager gives temperatures and cooling rates to IDS, which calculates the microstructural phenomena and the quality (Figure 1).

Case examples

Conclusions