城市水文过程因强烈的人类活动影响而发生了深刻变化,科学精细地模拟城市区域的产汇流过程是解析城市水问题机理的科学基础。在系统剖析城市水文模型原理的基础上,将城市复杂下垫面根据其透水特性划分为不透水单元、透水单元、半透水单元、伪透水单元、强透水单元、水域单元等六类基本单元,并构建了不同类型城市水文响应单元的水文特性曲线,基于圣维南方程组和Navier-Stokes方程提出了城市管网与河湖水系水动力学模拟的技术方案。在耦合城市水文响应单元的降水—截留—蒸发—入渗—产流模块、地表汇流模块、管网汇流模块、水系一维水动力学模块等基础上,以水循环过程为主线,将水文模型的径流输出作为城区一维管网、河道水动力模型的输入边界,实现水文模型与一维管网、河道水力学模型的集成。将单元水文模型通过城市管网和河湖水系等连接方式集成到城市水文模型系统中,弥补了现有城市雨洪模拟在水文学机理上的不足,可为城市排水防涝和海绵城市建设提供科学基础。
The urban hydrological process is markedly changed due to intensive human activities,while the scientific and precise simulation of runoff yield and confluence process within urban area is just a scientific basis for analyzing the mechanism of urban water issue. Based on a systematical dissection of the principle of the urban hydrological model,the complicated urban underlying surface is divided into six basis units,i. e. impervious unit,pervious unit,semi-pervious unit,pseudo-pervious unit,strong pervious unit and water-area unit,according to their previous characteristics,and then the hydrological characteristics of various urban hydrological responses are established. In accordance with Saint Venant equations and Navier-Strokes equations,the technical scheme for the hydrodynamic simulation on urban drainage network and river-lake water system is put forward herein. On the basis of coupling the precipitation-interception-evaporation-infiltration-runoff yield module,the surface confluence module,the drainage network confluence module and the one-dimension hydrodynamic module of water system,the runoff input for the hydrological model is taken as the input boundary for the one-dimension urban drainage network and river hydrodynamic model,thus the integration of the hydrological model with the one-dimension drainage network and river hydrodynamic model is realized. Integrating the unit hydrological models into the urban hydrological model system through the connection mode of the urban drainage network and river-lake water system,not only the deficiency of the existing simulation of urban storm water on hydrological mechanism can be made up,but a scientific basis can be also provided for both the urban drainage and waterlogging control and the construction of sponge city.