Effect of spatial distribution of runoff generation patterns on urban storm flood process simulation
The GRGM-SWMM model was constructed by coupling the grid runoff generation model(GRGM)and the rainstorm flood management model(SWMM).Taking the control basin of Zhongmou Hydrological Station on the Jialu River(including the central urban area of Zhengzhou City)as the study area,based on 18 measured rainstorm and flood data,the impact of spatial distribution of runoff generation modes on the accuracy of flood process simulation was explored.The results show that the spatial distribution of the infiltration-excess runoff generation pattern in the study area accounts for up to 72%,and the urban underlying surface is still dominated by the infiltration-excess runoff generation pattern.Compared to the SWMM that only considers the infiltration-excess runoff generation for runoff calculations,the GRGM-SWMM model,which considers different runoff generation patterns such as infiltration,saturation,and mixing,significantly improves the accuracy of peak flood discharge and flow process simulation.The relative error of runoff generation decreased by an average of 33.26%,and the determination coefficient increased by an average of 0.089.The root mean square error of simulated discharge also decreased by an average of 5.13 m3/s,while the Nash-Sutcliffe efficiency coefficient and the determination coefficient increased by an average of 0.227 and 0.207,respectively.
urban storm flood process simulationrunoff generation patternSWMMGRGM-SWMMZhengzhou City
国家科技期刊平台
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