In order to improve the control precision of strip coiling temperature for hot strip mill,the BP neural network was combined with mathematical model to calculate convective heat-transfer coefficient of laminar flow co...In order to improve the control precision of strip coiling temperature for hot strip mill,the BP neural network was combined with mathematical model to calculate convective heat-transfer coefficient of laminar flow cooling.The off-line calculated results indicate that the standard deviation of coiling temperature prediction is reduced by 22.84 % with the convective heat-transfer coefficient calculated by BP neural network.The prospects of this method for online application are bright.This method is more helpful to increasing the control precision of coiling temperature for hot strip steel.展开更多
Continuous steel strip casting lines in rolling miles are under active development.Due to high thermal losses the thin strip is cooling down very fast and therefore a sufficient heating system is necessary before fina...Continuous steel strip casting lines in rolling miles are under active development.Due to high thermal losses the thin strip is cooling down very fast and therefore a sufficient heating system is necessary before final rolling.Only induction heaters can realize the necessary fast heating of the strip and a good energy efEciency of heating.Because of induction heating lines for rolling mills are of extremely high power,all even small improvements in their design and operating modes have significant technical and economical effects.However,the heating lines need an optimal design of the complex induction systems and only numerical simulation is a way to solve the problem.Both two- and threedimensional numerical simulation approaches developed and applied for investigation and design of longitudinal induction heaters are described in the paper.The numerical models have been successfully used for development of modified coils allowing high efficient heating of thinner strip using the same operating frequency.Additionally electrical impedance of the modified coils has been provided on the level necessary for using the existing power supplies and matching equipment.Beside high electrical efficiency,the modified coils improve the temperature distribution over the strip width by increased heating of the strip edges.The optimized and modifies induction coils have been successfully tested in industrial line.展开更多
基金Item Sponsored by National Natural Science Foundation of China(50104004)
文摘In order to improve the control precision of strip coiling temperature for hot strip mill,the BP neural network was combined with mathematical model to calculate convective heat-transfer coefficient of laminar flow cooling.The off-line calculated results indicate that the standard deviation of coiling temperature prediction is reduced by 22.84 % with the convective heat-transfer coefficient calculated by BP neural network.The prospects of this method for online application are bright.This method is more helpful to increasing the control precision of coiling temperature for hot strip steel.
文摘Continuous steel strip casting lines in rolling miles are under active development.Due to high thermal losses the thin strip is cooling down very fast and therefore a sufficient heating system is necessary before final rolling.Only induction heaters can realize the necessary fast heating of the strip and a good energy efEciency of heating.Because of induction heating lines for rolling mills are of extremely high power,all even small improvements in their design and operating modes have significant technical and economical effects.However,the heating lines need an optimal design of the complex induction systems and only numerical simulation is a way to solve the problem.Both two- and threedimensional numerical simulation approaches developed and applied for investigation and design of longitudinal induction heaters are described in the paper.The numerical models have been successfully used for development of modified coils allowing high efficient heating of thinner strip using the same operating frequency.Additionally electrical impedance of the modified coils has been provided on the level necessary for using the existing power supplies and matching equipment.Beside high electrical efficiency,the modified coils improve the temperature distribution over the strip width by increased heating of the strip edges.The optimized and modifies induction coils have been successfully tested in industrial line.
