基于水汽通量放大法的可能最大暴雨估算改进方法

Improved Water Vapor Flux Amplification for Probable Maximum Precipitation Estimation

我国可能最大暴雨(PMP)估算方法以暴雨成因分析法使用最为普遍,传统的水汽通量放大法受风速日变化差异大影响,估算得到的PMP明显偏大。对此,采用"风向玫瑰图"改进传统水汽通量放大法,根据研究区域稳定风场情况对实测资料进行分组,确定暴雨水汽的主要入流方向和相应水汽通量值,并应用水汽通量放大倍比对实测典型暴雨进行放大推求可能最大暴雨(PMP)。以东南沿海某核电厂为例进行应用研究,并与其他方法计算结果对比,验证了所提方法的合理性。

Generally,cause analysis of rainstorm is the most widely used method in probable maximum precipitation(PMP)estimation in China.The traditional water vapor flux amplification method is greatly affected by the diurnal variation of wind speed,and the estimation of probable maximum precipitation is relatively large.Therefore,this paper presents an improved water vapor flux amplification method based on wind direction rose diagram.The measured data are divided into groups according to the direction of prevailing wind.And then the magnification ratio to maximize the high-efficiency storm is used to estimate the PMP.The improved approach is applied to a nuclear power plant in Southeast coastal City.Compared with other approaches,the rationality of the proposed method is verified.