A novel cooling system combining ultra fast cooling rigs with laminar cooling devices was investigated.Based on the different cooling mechanisms,a serial of mathematic models were established to describe the relations...A novel cooling system combining ultra fast cooling rigs with laminar cooling devices was investigated.Based on the different cooling mechanisms,a serial of mathematic models were established to describe the relationship between water flow and spraying pressure and the relationship between water spraying heat flux and layout of nozzles installed on the top and bottom cooling headers.Model parameters were validated by measured data.Heat transfer models including air convection model,heat radiation model and water cooling capacity model were detailedly introduced.In addition,effects on cooling capacity by water temperature and different valve patterns were also presented.Finally,the comparison results from UFC used or not have been provided with respect to temperature evolution and mechanical properties of Q235B steel grade with thickness of 7.8 mm.Since online application of the sophisticated CTC process control system based on these models,run-out table cooling control system has been running stably and reliably to produce resource-saving,low-cost steels with smaller grain size.展开更多
Abstract--Vapor compression refrigeration cycle (VCC) system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based ...Abstract--Vapor compression refrigeration cycle (VCC) system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based energy efficient control strategy which aims at maximizing the system efficiency is proposed. Firstly, according to the mass and energy conservation law, an analysis on the nonlinear relationship between superheat and cooling load is carried out, which can produce the maximal effect on the system performance. Then a model predictive control (MPC) based controller is developed for tracking the calculated setting curve of superheat degree and pressure difference based on model identified from data which can be obtained from an experimental rig. The proposed control strategy maximizes the coefficient of performance (COP) which depends on operating conditions, in the meantime, it meets the changing demands of cooling capacity. The effectiveness of the control performance is validated on the experimental rig. Index Terms--Cooling load, model predictive control (MPC), superheat, vapor compression refrigeration cycle (VCC).展开更多
基金Project(51034009)supported by the National Natural Science Foundation of China
文摘A novel cooling system combining ultra fast cooling rigs with laminar cooling devices was investigated.Based on the different cooling mechanisms,a serial of mathematic models were established to describe the relationship between water flow and spraying pressure and the relationship between water spraying heat flux and layout of nozzles installed on the top and bottom cooling headers.Model parameters were validated by measured data.Heat transfer models including air convection model,heat radiation model and water cooling capacity model were detailedly introduced.In addition,effects on cooling capacity by water temperature and different valve patterns were also presented.Finally,the comparison results from UFC used or not have been provided with respect to temperature evolution and mechanical properties of Q235B steel grade with thickness of 7.8 mm.Since online application of the sophisticated CTC process control system based on these models,run-out table cooling control system has been running stably and reliably to produce resource-saving,low-cost steels with smaller grain size.
基金supported by the National Natural Science Foundation of China(61233004,61221003,61374109,61473184,61703223,61703238)the National Basic Research Program of China(973 Program)(2013CB035500)+1 种基金Shandong Provincial Natural Science Foundation of China(ZR2017BF014,ZR2017MF017)the National Research Foundation of Singapore(NRF-2011,NRF-CRP001-090)
文摘Abstract--Vapor compression refrigeration cycle (VCC) system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based energy efficient control strategy which aims at maximizing the system efficiency is proposed. Firstly, according to the mass and energy conservation law, an analysis on the nonlinear relationship between superheat and cooling load is carried out, which can produce the maximal effect on the system performance. Then a model predictive control (MPC) based controller is developed for tracking the calculated setting curve of superheat degree and pressure difference based on model identified from data which can be obtained from an experimental rig. The proposed control strategy maximizes the coefficient of performance (COP) which depends on operating conditions, in the meantime, it meets the changing demands of cooling capacity. The effectiveness of the control performance is validated on the experimental rig. Index Terms--Cooling load, model predictive control (MPC), superheat, vapor compression refrigeration cycle (VCC).