Research Of Hydraulic Transition Process And Hydraulic Control For Water Diversion Project

The lack of water resources is the main reason affecting the rapid development of industry and the acceleration of urbanization.To solve the shortage of water resources in some areas and the imbalance between supply and demand,many large-scale water diversion projects have been built.Large-scale water diversion projects generally have the characteristics of large flow,complex terrain,various types of hydraulic structures,and difficult control and scheduling.In the actual water transfer process,the hydraulic parameters in pipeline and open channel also change a lot with the change of time,such as flow rate,water level beyond the design range,water hammer,backwater overflow,pipe explosion,and other situations may occur,and even affect the safety of dispatching in serious cases.In view of this problem,the research in this paper is as follows:Firstly,on the basis of studying open channel and pressure pipeline respectively,the one-dimensional unsteady hydrodynamic model that unify the open channel flow and pressure flow is established by using saint venant's equations,Preissmann slit method.Then this model is discretized by the semi-implicit discretization method on staggered grid in Hydroinfo hydraulic information system.Secondly,in order to verify the accuracy of the model,the numerical results are compared with the experimental data or analytic solutions of river network,transition flow and pipe network test cases.The numerical results show a good agreement with the experimental data and analytic solutions.Then,the regulation and storage project from Tuancheng lake to Miyun Reservoir in Beijing is taken as the research object.By defining and generalizing hydraulic structures such as gate valves,pumping stations and reservoirs as internal boundary conditions,the transition process of water conveyance projects is simulated.We mainly simulate the process of flow increasing and decreasing,the changing process of gate opening at different time and speed.Meanwhile,some hydraulic parameters such as water level and flow are analyzed.The analysis shows that when the flow rate decreases,the influence on the transition is greater.In addition,the longer the gate opening changes and the more uniform the opening speed,the less the influence of water conveyance process is.Finally,the process of water filling and the accident conditions are simulated.The filling time of each section and the hydraulic control in the filling process are obtained using the method of filling water in stages.Then,a sudden accident of the pumping station is investigated.the water level and flow changes of the water delivery system before and after the accident are obtained that can make appropriate operation in the system emergency,and also provide reference for the operation and control of the water delivery system.Therefore,it is significance to investigate the hydraulic transition process and operation control of water conveyance projects.