Research And Optimization Of Secondary Cooling Water Distribution Process For Continuous Casting

As an important part of metallurgical production,the advanced and efficient process of continuous casting is always an important guarantee for iron and steel enterprises to improve their production efficiency,optimize product quality and enhance market competitiveness.As the core technology of continuous casting,the secondary cooling process in the continuous casting process will directly affect the solidification process and the generation of defects.Therefore,it is of great significance to optimize the control process of secondary cooling in continuous casting for improving the automation and intelligence level of production line,promoting the reform of production structure,improving the capacity of casting machine,reducing defects of casting slab and meeting the requirements of sustainable development strategy.Firstly,based on the theory of solidification and heat transfer,the corresponding solidification heat transfer model is established to simulate the cooling and solidification process in the actual production of slab.The two-dimensional mathematical model of solidification heat transfer is established by considering the physical parameters such as thermal conductivity,specific heat capacity,solidus line temperature and liquids line temperature,and the finite difference method is used to solve the model,which provides the basis for the optimization of the secondary cooling water distribution process.Secondly,A new adaptive chaotic particle swarm optimization(ACPSO)algorithm is proposed to solve the problem of premature convergence and weak global optimization ability of standard particle swarm optimization.This method generates chaotic sequence by introducing cubic mapping to form chaotic particle swarm algorithm,and dynamically adapts to select inertia weight of the algorithm to solve problems such as local premature of the traditional algorithm and obviously speeds up the convergence speed.Compared with the other two methods(PSO and CFPSO),it shows the superiority of the algorithm in dealing with complex nonlinear problems.Thirdly,on the premise of considering the metallurgical criteria and casting process such as target temperature,temperature limit,temperature rise/drop rate,bulge limit,cooling water and drawing speed,etc.The improved adaptive chaos particle swarm optimization algorithm is used to optimize the secondary cooling water distribution.By comparing the optimized cooling water quantity,surface temperature and convergence rate,the good performance of the adaptive chaos particle swarm optimization algorithm in the secondary cooling process optimization is verified.Finally,research on non-uniformity of secondary cooling spray in continuous casting.Combined with the cooling performance of the secondary cooling nozzle and the solidification heat transfer characteristics of the slab,the selection and layout of the secondary cooling nozzle were optimized.And the simulation analysis proves that the temperature fluctuation of billet after optimization has remarkable improvement effect,and verifies the feasibility and validity of the spray uniformity improvement method in this paper.