基于物理机制的城市汇水单元降雨径流特性研究  

Physical mechanism-based study on rainfall and runoff characteristics of urban catchment unit

作　　者：任梅芳 宋利祥 庞博[3,4] 徐宗学 陈浩[3,4] REN Meifang;SONG Lixiang;PANG Bo;XU Zongxue;CHEN Hao(China Academy of Urban Planning&Design,Beijing100044,China;Pearl River Water Resources Research Institute,Guangzhou510611,Guangdong,China;College of Water Sciences,Beijing Normal University,Beijing100875,China;Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology,Beijing100875,China)

机构地区：[1]中国城市规划设计研究院,北京100044 [2]珠江水利科学研究院,广东广州510611 [3]北京师范大学水科学研究院,北京100875 [4]城市水循环与海绵城市技术北京市重点实验室,北京100875

出　　处：《水利水电技术（中英文）》2023年第9期37-47,共11页Water Resources and Hydropower Engineering

基　　金：国家重点研发计划“城市内涝演化规律与多尺度内涝精准模拟研究”(2021YFC3001401)。

摘　　要：【目的】城市下垫面透水面与不透水面之间错综复杂的空间关系使得城市地表降水径流关系变得更加复杂,与此同时,现阶段城市产汇流数值模型的产流计算模块仅停留在不透水地面产流量和透水地面产流量简单叠加的阶段。因此,有必要深入开展城市复杂下垫面径流机理研究,以便能够为城市内涝防治与治理提供理论基础和科技支撑。【方法】通过耦合一维垂向土壤水分运动方程和二维地表浅水方程,构建了适用于城市复杂下垫面的产汇流数值模型,结合室外水文观测试验对数值模型参数进行率定与验证。在此基础上,以汇水单元为计算尺度,就不同汇流模式下城市不透水面积比对城市地表产流系数的影响进行了定量描述。【结果】采用多场场地降雨径流监测结果对所建模型参数进行率定,且模型模拟精度验证结果表明,不同降雨径流过程的纳什效率系数分布在0.71~0.88之间,模型模拟效果较好。【结论】研究表明,在不同汇流模式下,不透水面积占比与径流系数呈线性函数关系,“有效不透水型”汇水单元的场次径流系数要略高于“无效不透水型”汇水单元的场次径流系数。[Objective]The intricate spatial relationship between the permeable and impermeable underlying surfaces within urban area makes the relationship between rainfall and runoff of ground surface more complicated.Meanwhile,the runoff producing Water Resources and Hydropower Engineering Vol.54 No.9 calculation module of the numerical model of urban runoff producing and concentration still stays at the stage of the simple super-position of the runoff yields of both the impermeable surface and the permeable surface.Therefore,it is necessary to deeply study the runoff mechanism of complicated urban underlying surface,so as to provide the theoretical basis and scientific and technical support for urban waterlogging prevention and control.[Methods]By means of coupling 1-D vertical soil water movement equa-tion with 2-D surface shallow water equation,the numerical model of runoff producing and confluence suitable for urban compli-cated underlying surface is established herein,and then the parameters of the numerical model are calibrated and validated in combination with the relevant outdoor hydrological observation experiment.On the basis of this,the impacts from the urban impermeable area ratios under different modes of runoff producing on urban surface runoff producing coefficient are quantitatively described through taking the catchment unit as the calculation scale.[Results]The parameters of the established model are cali-brated with the result of multi-site rainfall and runoff monitoring,while the verification result of the model simulation accuracy show that the Nash-Sutcliffe efficiency coefficient of different rainfall-runoff processes are distributed between 0.71 and 0.88 with better model fitting effect.[Conclusion]The study shows that the proportions of the impermeable area are linearly related to the runoff coefficients under different runoff producing modes,while the event runoff coefficients of the“effective impermeable type”catchment units are slightly higher than those of the“uneffective impermeable typ

关 键 词：城市洪涝 数值模型 Richard方程 浅水方程 

分 类 号：TV122[水利工程—水文学及水资源]