广义极值分布函数参数估计与设计洪水计算方法分析

Parameter Estimation and Design Flood Method in General Extreme Value Distribution

摘要: 广义极值分布是国际上水文频率计算普遍使用的分布线型。为分析广义极值分布推求设计洪水的适用性,总结了广义极值分布函数分布参数、统计特征参数、线性矩、离均系数等相互关系与计算方法,并与国内常用皮尔逊Ⅲ型分布在统计参数、设计成果等方面的差异性进行了对比分析。结果表明利用广义极值分布推求设计洪水具有一定的适用性,但推求校核洪水的合理性仍有待进一步研究。

Abstract: General extreme value distribution（GEV） is commonly used in international hydrology frequency analysis.In order to assess the feasibility of GEV in design flood, this paper summarized the relationship among distribution parameters, statistic character parameters, L-moment and dispersion coefficient of general extreme value distribution.Meanwhile, compares with P-Ш distribution in difference of statistic character parameters and design value. The results show that GEV is feasible for design flood, but the rationality for check flood calculation still need more research.