A Study On Water Polution Events Simulation Of Jingmi Cannal

Over recent years,several cases about accidental water pollution have arisen one by one in many areas of China.These accidents result in retinal water lack and gross economic losses as well cause enormous attention of society.Accordingly,many research institutions and related industrial technicians concentrate on the development and applied research concerning water resources and water quality model.The simulated water change trend provides more and more administrative units of water resources and water environment with the guide about how to adjust underground water,surface water and other water resources and water circumstances.After the operation of the middle line of the south-to-north water transfer project,in order to fully apply the water resources and increase the reserve of water resources in Beijing,Miyun Reservoir Diversion and Storage Project carried out in Beijing city conveys the water from south-to-north project into Miyun Reservoir through Jingmi Diversion Canal and Huairou Reservoir.This paper conducts a simulated analysis on the transmission of possible accidental water quality pollution along the canal in terms of the forward diversion or reverse diversion from Jingmi Diversion Canal and Huairou Reservoir to Tuancehng Lack through the combination of the water diversion from the south-to-north project into Miyun Reservoir.The major research content and conclusion are as follows:(1)As for the forward and reverse water diversions,the corresponding one-dimensional canal hydrodynamic model is established,Abbott Six Centric Implicit Method is applied to disperse one-dimensional canal hydrodynamic equation and elimination method is used to conclude the solution.(2)On the basis of the one-dimensional hydrodynamic model,a one-dimensional convection diffusion model is established,and implicit finite difference approach is used to solve the discrete equations.As for the forward and reversed water diversions,the model is used to simulate the change of pollutant transport proliferation in external sudden water pollution accidents in related risk points along the channel,and the simulation results are analyzed.(3)It can be seen through the simulation the process of water pollution that,regardless of a forward or reverse water diversion,the flow velocity within the channel always controls the scope of the dominant pollutants if relevant parameters and external boundary conditions remain unchanged.(4)When Jingmi Diversion Canal convey water in reverse way,the water flow form is of river type,the average monthly of water N/P is 27~78,TP concentration does not reach the threshold of overdue water body and the occurrence of sudden algal bloom is relatively low.However,there are certain uncertainties about the outbreak of algal bloom.Thus,it is a necessity to conduct real-time monitoring towards the water quality in canal in the time of frequent algal bloom.(5)Through numerical comparison and analysis,the result shows that the formulation of model and simulation of water pollution process can basically meet needs of the reference for the assessment and disposal of sudden water pollution accidents in Jingmi Diversion Canal,but also provide reference for the further discussion of future secure dispatching and management of canal water resources.