Study On Temperature Field Model And Optimal Tracking Control For Plate In Controlled-Cooling Process

Controlled-cooling is an important technology measure to improve the performance and quality of the product and develop the high additionally worthy product.The mathematical model of controlled-cooling technology is a key part, and the temperature field model is the most important part.Though the researching workers have opened out the mathematical model in nearly years at home and abroad, the key part of the mathematical model is not vended and few people researched deeply the temperature field mathematical model. So the concrete contents are as follows:(1) Combined one engineering item on controlled-cooling system in some medium and heavy plate plant, the cooling mathematical model and controll strategy of controlled-cooling system,especially of jet sort order effectting the cooling rate are studied.(2) Based on studying and summarizing the correlative theories of laminar cooling, basic heat-transfer process of plate is analyzed, and the controlled-cooling temperature field model based on Crank-Nicolson finite difference format is founded and further researched.It is more simple and practical by alternating direction method.(3) Added the correlative knowledge of optimal control theories, the temperature field model as a equation of state and linar quadratic cost functions are created for plate in controlled-Cooling Process and analyzed by using the Gamkrelidze minimum principle.Then we obtain five necessary conditions which are applied to getting the optimal controlled variable.(4) Combined the test datum in some medium and heavy plate plant with a procrdure of the conjugate gradient method, the optimal jet water density is achieved given thermal phs--ical properties,initial temperature and desired exit temperature of plates.Then with the help of Matlab 7.0, optimal tracking graphs of temperature field are simulated and analyzed.The sim--ulated figures show that connceting state-space medol of the temperature field with theopti--mal tracking control model is an effective way to improve the control precision of final cooling tempertaure.