丹江口水库运行水位优化方案比较OA

The Danjiangkou Reservoir serves as a key flood control project in the Han River basin.Its primary operational capabilities include navigation,hydropower generation,flood control,water supply,and ecological conservation.During the summer flood season,the flood-limited water levels are 160 meters,and during the fall flood season,they are 163.5 meters.With a storage capacity of 29.05 billion m3,the typical water level is 170 meters.Danjiangkou Reservoir's original design flood was far too large,resulting in significant water spillage during flood seasons and a low reservoir full-storage rate,failing to meet the new demands of integrated water resource management and efficient utilization in the modern era. Four typical flood events,namely"35 •7","64 •10","75 •8",and"83 •10",were selected to derive design flood hydrographs.Among them,1935 and 1975 were typical summer floods,and 1964 and 1983 were typical autumn floods.Based on seasonal flood staging and re-evaluated design flood results,the peak and volume amplitude method was used to derive 1 000-year design flood hydrographs.The Danjiangkou Reservoir's flood control operation rules were then used to calculate flood regulations for the 1000-year design flood hydrographs.The Muskingum algorithm was used to rout reservoir outflow discharge to the Huangzhuang hydrologic section,and superimposed the corresponding design inflow hydrograph in the Danjiangkou-Huangzhuang interval basin.According to original flood prevention standards,if the total peak discharge of the Huangzhuang hydrologic station does not exceed 40 000 m3/s,and the high flood control water levels of the reservoir during the summer and autumn flood seasons remain below 172.14 m and 172.20 m,respectively,the summer and autumn seasonal flood control water levels could be determined through flood routing calculation via trial-and-error method. Based on the Danjiangkou Reservoir's scheduling regulations and optimized scheduling rules,three operational schemes were formulated:Scheme A,original design flood limit water level based on scheduling regulations.Scheme B,seasonal flood control water level based on scheduling regulations;Scheme C,seasonal flood control water level based on optimized scheduling rules.Using daily inflow data series from 1954 to 2023 and other information,a comparative study on optimization schemes for operating water levels in Danjiangkou Reservoir was conducted. Results demonstrated that under the premise of ensuring flood safety,reservoir flood control water levels can be raised to 163.0 m(an increase of 3.0 m)in the summer flood season and 164.5 m(an increase of 1.0 m)in the autumn flood season.Compared with Scheme A,Scheme C can reduce 2.8 billion m3(-42.4%)spillage discharge,increase 400 million m3(+3.8%)water transfer volume and 400 million kW •h(+11.8%)power generation.At the same time,the number of full-storage years was increased from 10 to 22 years,and the daily ecological flow guarantee rate was raised to 93%(+14.8%).Overall,adjusting the operational water levels can significantly reduce spillage discharge,increase water transfer volume and power generation,improve the full storage rate,and guarantee the ecological flow rate.Hence,re-evaluating design floods and optimal operation water levels can significantly enhance the full-storage rate and comprehensive utilization efficiency of the Danjiangkou Reservoir.