Research On Operation And Dispatching Optimization Of Tidal Flow Project In Old Urban Area Of Nantong

In recent years,the Nantong municipal people's government and relevant departments have taken a series of measures to achieve the comprehensive renovation goal of" clear water flow,healthy rivers and lakes,beautiful ecology and harmonious people" and ensure the stable and harmonious development of the economy and society,and have achieved good results.Based on the existing water engineering facilities in the main urban area of Nantong city,this paper studies the hydrodynamic conditions of rivers,optimizes the regulation scheme of tidal flow,and makes a systematic and scientific planning for river system.A mathematical model for unsteady flow of river network in main urban area of Nantong is established in this paper.In this paper,Monte Carlo method and graph theory are applied to the calculation of river network.A random walk model is established and a method for solving unsteady flow in river network directly from energy equation is proposed.This method avoids solving large-scale matrices and needs less computer memory,and does not need to be numbered in a certain order between the branch and the river section.It is proposed.Based on the established mathematical model,the river network flow numerical simulation is carried out for several water transfer operation schemes of the tidal flat flow project in the main urban area of Nantong city,and the optimization of operation and dispatch is systematically studied.A total of 24 current operation schemes and 12 planned operation schemes were calculated for water diversion operation,each of which lasted 48 hours.The variation of water level,discharge and velocity with time in different sections of each river in the study area was obtained by calculation of all the schemes.The simulation results of river network flow under various operation schemes show that the hydrodynamic conditions in some areas around the Haohe river can be improved by making full use of the existing water engineering facilities and controlling the sluice and culvert around the Haohe river.The simulation results of river network flow with various operation schemes under the planned operating conditions show that the most obvious effect is to change the hydrodynamic conditions and enhance the self-purification capacity of the river,followed by the reasonable operation of culverts and sluices,and the worst effect is to increase the discharge of pumping stations.The Huafenghe pumping station with 8 m3/s diversion flow along the Tonglu canal and rengang pumping station with 6 m3/s diversion flow along the Yangtze river have the same overall effect on the improvement of hydrodynamic conditions,but the former is better in Hongqiao area and the latter is better in Haohe area.In addition,a new method for visualization of river network flow is also presented.According to the results of numerical simulation of river network flow,after Effects software is used to make water flow animation,which can visually display the movement state of river network flow,so that non-professionals can also understand the hydraulic characteristics of river network.