Study On Adaptive Control Model Of Water Quantity And Quality For Urban River

Along with the swift development of urban economy and the increasing urban expansion, the scale of water service in cities enlarged ceaselessly, following the more and more serious pollution of urban water environment. As we know, urban river is the important carrier for resources and environment;it relates to the existence of the city and confines its development. In the process of urbanization, which water environment treatment scheme is more rational and economical, and should be adopted;particularly, in the instance of the increment of wastewater, or when other unexpected disturbance destroys the ecological balance of the river, what should be done to promote the water quality returns to the expectation and the quantity and quality of the river achieve self-adaption is worth considering.In this paper, the water environment features of city of Lianyungang are analyzed. Based on this, a mathematical model of hydraulic and water quality for plain tidal river network that is suitable to the research area is established. The computing results by the model show that in present status, the basic water environment demands can be satisfied by diversion of stream to urban rivers. Furthermore, considering the developing requirements, an adaptive control model of water quantity and quality for urban river has been constructed. The model is a self-optimizing control model based on system engineering;it has complex performance indexes and describes the state equations about the water quantity and quality in the urban river system. In the model, river is generalized to several adjustable systems, and each system is one reach. For each reach, its known disturbance is the water concentration of the upper reach, and unknown disturbance is the reach's pollution discharge. The controlled object of the model is the lower reach, and its water concentration and pollution discharge are the control measuration. In the process of control, Lagrange multiplier is used. By the control algorithm, the model can track the predefined trajectory during the continuous comparison with the performance indexes and decision, and the optimal scheme of water environment treatment can be given by the control results. As the application of the model, calculation has been done by taking the forecasted pollution discharge of city of Lianyungang in the planning year-2010 as the disturbance, and the planning water quality standards as the control object. Results show that in the instance of the increment of wastewater, according to the optimal control trajectory given by the model, under the consumption of control force, the urban river can return to the expected quality, and the self-adaption of water quantity and quality can be achieved.Besides, an adaptive control system of water quantity and quality for urban river using ASP is developed herein. In the development of the system, database management and graphics interactivity technology are adopted. Based on B/S structure mode, the control procedure is visual, and also the interactive web server applications as well as the informatization and networked of management are realized.