水文模型参数综合敏感性系数分析

Parameters Sensitivity Analysis of Hydrologic Model

水文模拟中的双超产流模型需要一系列具有空间分布特征的参数对流域产流过程进行模拟。以榆社水文站10场次洪水为研究对象,以双超模型参数经验初值作为基值,采用扰动分析法对参数的敏感性进行分析优化。通过参数调节与模拟计算,得到各参数对洪水的敏感性系数,借助变异系数法算出模型参数的综合敏感性系数。研究表明,模型参数对应不同的水文要素,其敏感性系数与相关性会有所改变,各水文要素下参数综合敏感性系数大小排序为Sr>b>Ks>α_0>σ≈c。

A series of parameters which have spatial distribution characteristics is required in double-excess runoff generation model to simulate the process of watershed runoff. Taking ten floods in Yushe Hydrological Station as research object, the sensitivity of parameters is analyzed and optimized by using perturbation analysis method, in which, the empirical values of parameters of double-excess runoff generation model are used as base values. The sensitivity coefficients of various parameters on flood are obtained through parameter adjustment and simulation scenarios, and the comprehensive sensitivity coefficient of model parameters is also calculated by using variation coefficient method. The analysis results show that the sensitivity coefficients and correlations of model parameters will change when it is in different hydrological elements, and the magnitude of comprehensive sensitivity coefficient of parameters under different hydrological elements has a order of Sr〉b〉Ks〉α_0〉σ≈c.