Study On The Ralationship Between Rainfall And Flood And The Regulation Of Storage And Discharge Of Main Medium Sized Reserviors In The Upper Reaches Of Baiyangdian

There are 6 large reservoirs,8 medium reservoirs and 129 small reservoirs in the upper reaches of Baiyangdian,which play an important role in regional control and flood control safety and water resources utilization in xiong’an new area.Based on the long-term rainfall and flood data,this paper analyzes and controls the runoff and confluence laws of the basin,and formulates the regulation scheme of different standard floods,which provides technical indicators for the safe operation of the reservoir and flood control and disaster reduction.The main conclusions of this paper are as follows:(1)Through to the analysis of the basic situation of the upstream water system of Baiyangdian,the importance of medium-sized reservoirs to the relationship between rainfall and flood and the regulation of storage and discharge is clarified.On this basis,the basic hydrological data of three typical reservoirs,Longtan,Wanglong and Leizi,are collected to prepare the basic data for the analysis of reservoir storage and discharge regulation and control.(2)Based on the precipitation and runoff data of Longtan,Wanglong and Leizi reservoirs from 1988 to 2018,the rainfall and runoff variation law of Longtan Reservoir was studied.The area rainfall with different frequencies was calculated to calculate the net rainfall.Five frequencies of 0.1%,1%,4%,20%and 50%were taken as area rainfall.The corresponding area rainfall values of Longtan Reservoir control basin are 1100mm,869mm,749mm,532mm and 421mm,respectively.The corresponding area rainfall values of the control basin of Wanglong reservoir are 1120 mm,894 mm,753 mm,556 mm and 423mm,respectively.The corresponding area rainfall values of Leizi reservoir control basin are 1330 mm,1020 mm,838 mm,582 mm and 421mm respectively.(3)The P+Pa-Rs correlation diagram is drawn by inversing the inflow flood process.When the runoff depths are 4%,20%and 50%,the corresponding runoff depths of Longtan Reservoir control basin are 160mm,56mm and 25mm;that of Wanglong reservoir are 98mm,56mm and 39mm;that of Leizi reservoir are 163mm,65mm and 34mm.(4)The flood process with different frequencies is deduced,and four frequencies of 0.1%,1%,4%and 20%are used to calculate the reservoir flood peak and flood volume.The corresponding peak discharges of Longtan Reservoir are 1260m3/s,657m3/s,496m3/s and 72m3//s;the corresponding peak discharges of Wanglong reservoir are 967m3/s,494m3/s,3 78m3/s and 33m3/s;the corresponding peak discharges of Leizi reservoir are 915m3/s,475m3/s,392m3/s and 64m3/s,and the design flood is finally determined Process line.(5)According to the hydrological data of water levels,storage capacities and discharges of three typical medium-sized reservoirs,the reservoir characteristic curve is drawn,which mainly includes the relationship between water level and storage capacity and the relationship between water level and discharge capacity.The flood discharge of instantaneous water level can be adjusted according to this relationship.Based on the analysis of flood regulation parameters of three reservoirs,such as reservoirs,water levels and opening time of flood discharge equipments,the flood period is established.Based on the hydraulic parameters of the spillway,the maximum discharge of the spillway is determined when the reservoir meets the once-in-a-thousand check flood and a hundred year design flood according to the hydraulic parameters of the spillway.This paper analyzes the operation mode of three medium-sized reservoirs,and puts forward the operation schemes of different hydrological years for the reservoirs after rechecking the flood resistance capacity of the reservoirs,and determines the storage and discharge control modes of the reservoirs,so as to provide theoretical basis for the safe flood control of the reservoirs.