感潮河段交汇区三维水流特性数值模拟研究——以宁波三江口为例  

Numerical Simulation Study on Three-dimensional Flow Characteristics in the Confluence Area of Tidal Reach--A Case Study of Sanjiangkou in Ningbo City

作　　者：胡涛 HU Tao(Guangdong Research Institute of Water Resources and Hydropower, Guangzhou 510635, China)

机构地区：[1]广东省水利水电科学研究院,广东广州510635

出　　处：《广东水利水电》2020年第11期46-51,共6页Guangdong Water Resources and Hydropower

摘　　要：水流交汇处通常是河网间水位、污染物等水流要素的控制节点,对区域内防洪、航运、水环境等意义重大,加之其复杂的三维水流特性,长期以来都是水利学科研究的重点和难点。该文采用Delft-3D数值模拟软件建立了宁波三江口交汇区二、三维耦合数学模型,利用洪、枯季大潮水文资料对模型参数进行了率定。在此基础上,以洪季大潮为例,分析了感潮河段交汇区三维水流特性。结果表明:受交汇口地形的影响,随水深增加交汇口内两股水流的分界线不再明显,交汇后河道主流位于下游河道中部;两股水流交汇前后并没有形成明显的二次流。此外,水流在经过三江口时,水流流速在对应时刻的下游河道发生重分布,不同水深间的流速梯度均有减小。The confluence of water flow is usually the control node of water level,pollutants and other water flow elements between river networks.It is of great significance to flood control,navigation,and water environment in the region.In addition,its complex three-dimensional flow characteristics have long been the focus of water conservancy research.difficulty.In this paper,with the help of Delft-3D numerical simulation software,a two-and three-dimensional coupled mathematical model of Ningbo Sanjiangkou is established,and the model parameters are calibrated using the hydrological data of flood and dry seasons.On this basis,the three-dimensional flow characteristics of the confluence area of the tidal reach are analyzed under the condition of the flood season.The results show that,affected by the topography of the junction,as the water depth increases,the boundary between the two currents in the junction is no longer obvious,and the main stream of the river is located in the middle of the downstream channel after the intersection;there is no obvious secondary flow before and after the two currents meet.In addition,when the water flows through the Sanjiangkou,the flow velocity is redistributed in the downstream river channel at the corresponding time,and the velocity gradient between different water depths is reduced.

关 键 词：感潮河段 交汇水流 数值模拟 三维水流特性 Delft-3D 

分 类 号：TV147.4[水利工程—水力学及河流动力学]