HEC-HMS模型在青山河流域洪水模拟中的应用

Application of HEC-HMS Model in Flood Simulation of Qingshan River Basin

在中小流域山洪灾害预警中实现快速模拟洪水过程的重要性日益凸显。运用HEC-HMS模型结合GIS技术构建青山河流域分布式水文模型,以DEM数据为基础提取水系特征将小流域网格化,选用初损常损法及斯奈德单位线法计算地表径流,以非线性boussinesq法模拟基流消退过程,再以马斯京根法进行河道演算。采用5场实测洪水资料率定模型参数,13场洪水进行预报检验,结果显示验证期洪水洪峰流量误差均小于20%,峰现时差均小于3 h,确定性系数除2场小于0.7外,其余均达到0.7以上。表明HEC-HMS模型在本流域模拟中准确性高、稳定性好,满足洪水预报要求,对于探索小流域次洪模拟分析具有较大的应用价值。

It is more and more important to realize the fast simulation of flood process in the early warning of mountain flood disaster in small and medium river basins.This paper builds a distributed hydrological model for Qingshan River Basin by combining HEC-HMS model with GIS technology,extracts the characteristics of river system and conducts gridding on small basin based on DEM data,calculates the surface runoff by initial and constant loss method and Snyder unit hydrograph method,simulates the process of base flow recession through nonlinear boussinesq method,conducts the channel routing by Muskingum method,calibrates the parameters with the past 5 measured flood data,as well as verifies the prediction results by 13 floods.The simulation results show that during the verification period,the errors of peak discharge are all within 20%,the time difference for peaks is less than 3 h,the certainty coefficient is less than 0.7 for only 2 floods,and above 0.7 for others.The results show that with high accuracy and stability,the HEC-HMS model for flood simulation in this river basin conforms to the requirements of the flood forecast,which is of great application value for the exploration of small basin flood simulation and analysis.