Int. J. Engineering Systems Modelling and Simulation, Vol. 2, No. 4, 2010 211 Copyright © 2010 Inderscience Enterprises Ltd. Computationally efficient numerical technique for primary cooling zone of thin slab continuous casting Niloy K. Nath* Department of Metallurgy and Materials Science, College of Engineering Pune, Pune – 411005, India E-mail: nkn.meta@coep.ac.in *Corresponding author Smita Kamble Department of Materials Engineering, Indian Institute of Science, Bangalore – 560012, India E-mail: smitakam17@gmail.com Abstract: Thin slab continuous casting process can be controlled by the water flow rate through the copper mould to obtain the proper shell thickness for a given casting speed. To achieve this, 2D model for the liquid metal flow in the strand and water flow through the mould is developed using stream function and vorticity formulation. The main advantage is faster computation, which is very important for process optimisation, and real-time modelling for process control. The funnel type shape of the mould is efficiently taken into consideration by using body fitted coordinate system. The detailed CFD-based model can be used for analysing the process parameters and variables like heat transfer through the mould flux, casting speed and superheat. The model can be easily adapted for wide range of casting process like slab and billet casting and thin strip casting. Keywords: thin slab casting; stream function and vorticity; primary cooling zone; mould flux; shell thickness. Reference to this paper should be made as follows: Nath, N.K. and Kamble, S. (2010) ‘Computationally efficient numerical technique for primary cooling zone of thin slab continuous casting’, Int. J. Engineering Systems Modelling and Simulation, Vol. 2, No. 4, pp.211–216. Biographical notes: Niloy K. Nath is a Professor in the Department of Metallurgy and Material Science, College of Engineering Pune, India. He received his PhD from IIT Kanpur (1995), and Postdoctoral Fellow from Universidade Federal Fluminense, Volta Redonda, Brazil (1995 to 1997). He is a Scientist in Tata Research Development and Design Center, Pune, India (1997 to 2005); Research and Development Division of Kalyani Carpenter Steel, India (2005 to 2008). His current research interests include process modelling and optimisation, iron and steelmaking, and reaction kinetics and thermodynamics. Smita Kamble is a PhD Research Scholar in the Department of Materials Engineering, Indian Institute of Science Bangalore. She has completed her graduate studies from the Department of Metallurgy and Material Science, College of Engineering Pune, India (2005 to 2010). Her research interest includes metallurgical process modelling and numerical simulation. 1 Introduction In the present day, competitive market, it is very important to implement process control and process optimisation for improving the quality and productivity of continuous casting process. Computer models used for real-time or online prediction and control of the process are fundamental tool for this effort. Accurate online control and prediction allows flexibility in caster operation and capability to vary casting speeds, while keeping process parameters like surface temperature and solidification end point or metallurgical length within the desired range. During the continuous casting process, fluid flow and heat transfer in the strand, where solidification and shell thickness formation is very critical, and heat flow through the copper mould is controlled by the water flow rate through the mould (Santillana et al., 2008; Hebi et al., 2006). Optimum shell thickness is important for the continuous casting process, since if the shell thickness is too small then bulging or crack formation in the strand may take place disrupting the smooth operation of the process, and if the shell thickness is too thick transverse crack formation may take place, mainly in the Peritectic grade steels. The