Research On Staged Limited Level Of Baishi Reservoir Based On Fuzzy Set Theory

Liaoning Province is one of the severely water-scarce provinces in northern China.The contradiction of water resources shortage is even more prominent.The distribution of water resources in our province is extremely mismatched with the strategic layoutof economic development,which has seriously restricted the sustainable development of the economy in our province.Relying on advances in science and technology,giving full play to the role of regulating and accumulating existing reservoirs,digging up the potential for reservoir storage,and using flood water resources without increasing the risk of flood control,is of great significance to alleviating the contradiction between supply and demand of water resources andimproving the utilization rate of water resources.The flood control water level is an important factor affecting flood control operation of reservoir,and selecting the appropriate limited water level of flood control in reservoir filling is an effective way to deal with the contradiction between flood control and profiting of the reservoir.Therefore,it is necessary to study the flood control level of the reservoir on the basis of ensuring the safety of the reservoir.In this paper,based on the review of the study of the application of water level adjustments at home and abroad,the Baishi reservoir in the Daling River Basin was studied.The study was carried out from the division of flood season,the calculation of the flood control water level,and the risk analysis of the flood control water level adjustment.According to the actual situation of Baishi Reservoir,the set pair analysis method and the fuzzy analysis method were used to divide the flood season of Baishi reservoir.Combined with the current flood season staging scheme of Baishi reservoir,the following staging results are obtained:June 1 to July 10 are the pre flood season,July 11 to August 21 are the main flood season,and August 22 to September 30 are the post flood season.Based on the division of flood season,the flood control water level of the reservoir is calculated,and the flood control capacity is calculated from the theoretical membership degree obtained by fitting.The flood control water level of the reservoir is determined according to the relationship curve of water level storage capacity.Based on the theory of risk analysis,taking Baishi Reservoir as the research object,the risk of the reservoir after raising the limit water level was studied.In accordance with the proposed different limit water level schemes,under the selected limit risk rate control indicators,the limit risk rate analysis method is used to calculate the corresponding limit risk rate for different flood control water level.On the premise of ensuring the safety of the reservoir itself,determine the maximum limit water level that the reservoir can reach when it encounters a certain frequency flood.