Research On Joint Water Dispatching Of Water Supply Project From Songhua River Based On Coordinated Optimization Of Trunk And Branch Lines

The central region of Jilin Province is the core area of the province’s social economy.Under the guidance of the policy of cultivating the central city,the population and industry continue to gather in the central city.Due to the increase of urban population and the landing of industrial enterprises,the water demand for urban life and production is increasing.The existing water source can not meet the growing water demand of the city.The city began to occupy a large amount of agricultural and ecological water,resulting in the contradiction between urban living and production water,agricultural irrigation water and ecological environment water.In order to alleviate the contradiction between supply and demand of water resources in the central region and ensure the sustainable development of regional social economy,the Jilin provincial government decided to implement the water supply project of the central city of Jilin Province,from the Fengman Reservoir in the upper reaches of the Songhua River to the central region of Jilin Province.For this large-scale water diversion project,how to allocate water resources is a core issue,and the project includes multiple key nodes in the water source area and the water receiving area.The scheduling operation problem is very complicated,so scientific and reasonable water allocation will become the key to project benefits.Therefore,this paper makes an in-depth analysis of the joint operation of the water source area and the water receiving area of the central water diversion project.Through the prediction of water supply and demand,the water demand and water supply potential of the water receiving area in 2030 are analyzed,and the water supply and demand balance analysis is used to judge the water shortage situation and distribution characteristics of the water receiving area.By constructing the optimal operation model of the reservoir in the water receiving area and the joint operation model of water quantity,the joint operation of local water and diversion water is studied,and the reservoir in the water receiving area is fully utilized to improve the comprehensive utilization rate of local water resources and the comprehensive utilization benefit of the central water diversion project.The main research results include the following three aspects:(1)On the basis of consulting and combing the relevant literature at home and abroad,this paper analyzes the research status of water supply and demand prediction and optimal allocation of water resources,and summarizes the existing shortcomings and future development trends.The basic data of natural geographical environment,social economy and water resources in the water receiving area were collected and sorted out,and the development and utilization of water resources in the water receiving area were analyzed.Through the analysis of water supply and demand in the current year of 2019,the water shortage degree and distribution form of water supply towns in the water receiving area are revealed under the condition of returning agricultural and ecological water occupied by the city and reasonable exploitation of groundwater.The total water shortage under the multi-year average condition and the P=95%inflow year were 414.55 million m~3and 495.01 million m~3,respectively,and the overall water shortage degree was 41%and 49%,respectively.(2)Based on the relevant planning,historical water consumption data and related research reports of cities and counties in the water supply towns of the water receiving area,the quota method,Grey Markov model and regression analysis method are used to predict the water demand in 2030.The results of the quota method are selected as the water demand prediction results,and the total water demand is 1670.16 million m~3.The water supply potential of surface water,groundwater,reclaimed water and other water sources in the water receiving area in 2030 is analyzed.The total water supply in the years of multi-year average and P=95%incoming water is 821.46 million m~3and 741.47 million m~3respectively.Through the analysis of water supply demand balance,the water shortage situation of water supply towns in 2030 is studied and judged.The total water shortage in the years of multi-year average and P=95%inflow is 865.71 million m~3and 946.17 million m~3respectively,and the overall water shortage degree is 52%and 57%respectively.(3)The reservoir optimal scheduling model is established,and the immune evolutionary algorithm and particle swarm optimization algorithm are organically combined to construct a particle swarm optimization algorithm based on immune evolution.The model is solved to obtain the scheduling diagram of each storage reservoir in the water receiving area.By combining the joint operation model of water quantity at water diversion outlets with the coordination and optimization model of trunk and branch lines,a joint operation model of water quantity is constructed,which makes full use of local storage reservoirs to realize the joint operation of water diversion and local water resources,unified management and system configuration of various water resources,and the joint operation scheme of water quantity under different conditions in 2030 level year is obtained.The water diversion volume of the central water diversion project in the years of multi-year average and P=95%incoming water is 857 million m~3and 930 million m~3respectively.The guarantee rate of domestic water and ecological water for urban residents in each trunk line reaches 100%,and the guarantee rate of production water is above 96%.