基于Copula函数的瓯江设计潮位过程研究  

Research on the Design Tide Curve of Oujiang River based on Copula Function

作　　者：林乐曼 周倩倩 LIN Leman;ZHOU Qianqian(Wenzhou Water Conservancy Development&Research Center,Wenzhou 325000,Zhejiang,China;Wenzhou Water Conservancy Bureau,Wenzhou 325000,Zhejiang,China)

机构地区：[1]温州市水利规划发展研究中心,浙江温州325000 [2]温州市水利局,浙江温州325000

出　　处：《浙江水利科技》2022年第3期11-16,共6页Zhejiang Hydrotechnics

基　　金：温州市基础性科研项目(2020R0107)。

摘　　要：在推求设计潮位过程中,同频率法因高潮位与潮差为独立分布的假定存在主观性和随意性。针对这一问题,以瓯江为研究对象,根据温州站1970—2018年的潮位,利用Copula函数构建年最高潮位和同期潮差的二元联合分布,分析不同频率高潮位和潮差的组合风险,构造给定频率设计高潮位下,条件最可能潮差模型,并首次利用遗传算法求解,然后按高潮位和条件最可能潮差组合双重控制求得设计潮位过程线。结果表明:瓯江高潮位与潮差不具备同频率的特性,低频率的高潮位与高频率的潮差遭遇概率更高;应用遗传算法求解的条件最可能模型是可行的。2~200 a重现期的设计高潮位下,条件最可能潮差为1.90~2.34 a一遇,基于该方法推求的设计潮位过程线较同频率法统计基础更强、更合理,用于防洪排涝工程设计计算安全裕度更大。In the calculation of the design tide curve,the same frequency method is subjective and arbitrary because of the assumption that high tidal level and tidal range are distributed independently.To deal with this problem,this paper took the Oujiang River as the research object.Based on the tide level data of Wenzhou Station from 1970 to 2018,the binary joint distribution of annual maximum high tidal level and tidal range was constructed by using Copula function.Then this paper analyzed the combined risk of high tidal level and tidal range at different frequencies.Further more,the model of the most likely tidal range was constructed when a given frequency high tidal level happened and genetic algorithm was used to slove the model for the first time.Then design tide curve was obtained based on the combination of high tidal level and the most likely tidal range.The results show that the high tidal level and tidal range of Oujiang River do not have the same frequency characteristics,and what’s more,the probability that high tidal level of low frequency encounters tidal range of high frequency is much higher than tidal range of low frequency.It is proved feasible to apply genetic algorithm into solving the most likely tidal range model and it is analysed that when the high tidal level of 2~200 a return period happens,the tidal range of 1.90~2.34 a return period is most likely to occur.In a word,compared to the same frequency method,the method used in this paper is more reasonable for its good statistical basis and safer for flood control and drainage engineering design.

关 键 词：Copula联合分布 瓯江 设计潮位过程 设计高潮位 条件最可能潮差组合 遗传算法 

分 类 号：P731.23[天文地球—海洋科学] TV11[水利工程—水文学及水资源]