湖北省小流域洪水汇流参数复合分析

Fitting analysis for flood confluence parameters of small watershed in Hubei Province

基于同一小流域各场洪水的汇流参数,即纳希瞬时单位线(IUH)参数(n、k)随造峰雨强度及时空分布呈一定规律变化的特点,根据湖北境内河流、湖泊、水库实测暴雨洪水资料复合场次洪水汇流参数,综合得出设计条件下的流域汇流参数。结果表明,复合计算洪水与实测洪水较为接近,其复合优化参数明显优于矩法参数,是适用于目前湖北地区洪水资料短缺的小流域设计洪水计算的有效方法之一。

The confluence parameters for different floods in a small watershed （ namely, the parameters n, k of Nash instanta- neous unit hydrograph） vary in a certain law with peak rainfall intensity and spatial - temporal distribution. According to sur- veyed data of storm and flood of the rivers, lakes and reservoirs in Hubei Province, the flood confluence parameters under design condition are analyzed. The results show that the calculated floods are similar with observed floods, and the fitted optimized pa- rameters are obviously superior to the parameters calculated by moment method. Therefore, the fitting analysis for confluence parameters is one of the effective methods for design flood calculation of a small watershed in Hubei Province under the circumstances of lacking flood data.