Applicability Analysis of Generalized Unit Hydrograph in Flash Flood Simulation
The generalization of the watershed's contribution to net rainfall storage as M equivalent linear reservoirs in parallel provided a new method for catchment calculation.To test its applicability in flash flood simulation,four small tributaries of Huaihe and Yangtze rivers were selected as the study objects and the rainstorm flood process was compared with Nash unit hydro-graph method.The results show that the simulation reaches the standard of Class B accuracy requirement,but from the evaluation indexes,the average Nash efficiency coefficient,peak present time and its passing rate of the generalized unit hydrograph(0.79,0.90 h,98.30％)are better than the Nash unit hydrograph(0.75,1.09 h,94.34％).Moreover,it integrated the topographic and geo-morphological features of the watershed,which can better characterize the watershed catchment characteristics and has strong appli-cability,providing a new idea for domestic flash flood hazard warning and forecasting.
generalized unit hydrographflash flood simulationparameter optimizationsurface confluence
万方数据
维普
