A Near‐Process 2D Heat‐Transfer Model for Continuous Slab Casting of Steel

Abstract

Continuous casting has become a highly developed technology for producing steel grades with the highest surface and internal quality. Adequate numerical simulation tools have accompanied this enormous progress in process development with practical relevance for continuous casting. Computation modeling so far addresses a wide variety of the phenomena involved such as heat transfer, fluid flow, thermomechanics, phase transformations, and all aspects of product quality, as recently reviewed by Thomas. [1] For process control, standard solidification models solve the heat-transfer equation in 2D or 3D under stationary or transient boundary conditions and provide information about shell growth and temperature distribution. [2] For online process models, the quality of the thermal boundary conditions and the thermophysical properties of the cast steel grade is decisive for the accuracy of the calculation results.The working group M 2 CC at Montanuniversitaet Leoben has been working on the experimental and numerical simulation of quality-relevant aspects of casting for decades. Meanwhile, the characterization of phase transformations in steels [3][4][5] and the assessment of thermodynamic databases [6] have become a further research focus. The numerical models, databases, measurement techniques, and laboratory experiments developed are linked in the noncommercial offline "casting development platform" m 2 CAST, schematically illustrated in Figure 1. [7] The main emphasis behind the solidification model m 2 CAST is the transfer of process information to lab experiments and vice versa. The general concept and individual steps can be summarized as follows:Thermodynamic data in the material module m 2 MAT is based on extensive internal differential scanning calorimetry (DSC) measurements and thermodynamic calculations, for example, by FactSage 8.0 software and its databases. [8] The calculated thermophysical properties of the steel grade of interest, for example, phase fractions, heat capacity, thermal conductivity, and density, are required to solve the heat conduction equation.In the caster configurator, the slab dimensions and geometry, that is, thickness, width, and casting gap, must be defined along with the mesh size.

Graphics‐Processing‐Unit‐Accelerated 3D Online Heat Transfer and Solidification Model for Continuously Cast Slab

“…In fact, in secondary cooling, the cooling intensity on the surface of slab is not uniform due to the nozzle arrangement, [ 25–27 ] which makes these models can hardly reflect the influence of nonuniform cooling on heat transfer and solidification. Recently, some researchers have begun to introduce the effect of nonuniform cooling in CC process, such as Ramírez‐lópez et al [ 28 ] and Berhard et al [ 29 ] With the development of computational technologies and online models, it's time to build a more accurate and high‐fidelity model to predict the nonuniform solidification in real time.…”