Application of a Solidification Mathematical Model and a Genetic Algorithm in the Optimization of Strand Thermal Profile Along the Continuous Casting of Steel

ABSTRACT

This work presents an optimization method based on a genetic algorithm applied to continuous casting process. A simple genetic algorithm was developed, which works linked to a mathematical model permitting the determination of optimum values for the water flow rates in the secondary cooling zones. First, experimental data (industrial) were compared with simulated results obtained by the solidification mathematical model, to determine the metal/cooling heat transfer coefficients along the machine by the inverse heat conduction problem method. The industrial data concerning surface strand temperature were obtained by using infrared pyrometers along a continuous caster machine during casting of both SAE 1007 and 1025 steels. In a second step, these results were used by a numerical code based on a genetic algorithm for determining optimum settings of water flow rates in the different sprays zones, which are conducive to the best quality of the solidified strand. The simulations were carried out by analyzing the solidification process during continuous casting to attain metallurgical restrictions concerning the reheating of strand surface temperature and metallurgical length.

Key Words:

• Continuous casting of steel
• Genetic algorithm
• Mathematical modeling
• Optimization methods

ACKNOWLEDGMENTS

The authors acknowledge financial support provided by FAPESP (The Scientific Research Foundation of the State of São Paulo, Brazil), CNPq (The Brazilian Research Council) and Ac¸os Finos Piratini–Gerdau Steel Co. Tiago Machado Ferraz is also acknowledged for helping with the computer programming.