交汇口支流水动力特性数值模拟研究

Numerical simulation of hydrodynamic characteristics at tributary confluence

城市水工建筑物多建于穿城而过的小型支流中,有着为城市防洪抗旱,美化城市水环境等重要作用。运用RNG k-ε紊流模型对明渠小型支流河口进行了数值模拟,采用VOF方法处理自由表面,分析了与大型河流交汇处不同形态小型支流的水位、流速、紊动能耗散率和床面剪切力等水流特性。结果表明:支流流量和支流上游河道走向是引起水流特性改变的重要因素。研究成果可为城市汇流口小型支流河道水工建筑物的设计建造、河道整治提供参考。

Urban hydraulic structures, mostly built in the small tributary streams of the city, play an important role in the city flood control and drought relief and urban water environment beautification. Adopting VOF method to deal with the free surface, RNG turbulence model was used to simulate the flow characteristics of tributary confluence. The water flow characteristics such as water level, velocity, turbulent energy dissipation rate and bed shear force under different confluence forms of small tributaries with large - scale river were analyzed. The results show that the main factors affecting the flow characteristics are the tributary flow and the upstream trend of tributary river. The research results can provide reference for the design and construction of the hy-draulic structures built on the urban small tributaries in confluence area.