A Research Based On A Method Of Surface Temperature-feedback Continuous Casting Slab Secondary Cooling Control

Continuous casting process is the one of most important techniques in steelmaking industry. The efficiency and quality of continuous casting process directly influence the final production and characters of various steel grades. The advanced secondary cooling crafts and control level can improve the production efficiency and the quality of casting blank enormously. The main purpose of this article is developing the dynamic secondary cooling system which has practical significance in view of the secondary cooling process of slab continuous caster.This article establishes the solidification and transfer mathematical model based on the Elementary theory of metal solidification and heat transfer. Based on the limited volume integration and took Alternate Implicit Difference (ADI) method as core algorithm, It establishes two-dimension slice trace model that the heat is transfer along the width and thickness directions of casting slab. Furthermore, it adopts TDMA algorithm to solve numerical problem. Considering four different kinds of heat transfer boundary conditions with the real nozzle spray flux, rolls contact and radiation in secondary cooling region, the distribution of three-dimensional temperature and solid fraction in slab is predicted. This paper bases on the mathematical model of two-dimensional slab solidification heat transfer which has been established to calculate the water setting-value of secondary cooling, and adopts two-points-divided searching method to search the setting value.The dynamic secondary cooling control system which were set up for the medium thin slab caster is developed based on the transient two-dimensional heat transfer theory, adopted object-orient method and under Visual C++6.0 translation environment. The system divides into dynamic secondary cooling process module and dynamic control module. The craft module is used to calculate the real-time distributions of temperature and solid fraction, while the control model was used to adjust cooling water flow rates to keep stable slab surface temperature accorded with the aim value in alterable conditions. The system achieves the data transportation with the level-1 system to control the cooling water flow rates.