基于无结构网格的瓯江口三维盐度数值模拟  

Three-dimensional salinity modeling of Oujiang river estuary based on unstructured mesh

作　　者：林伟波[1,2] 王义刚[1] 朱明敏[1] 

机构地区：[1]河海大学海岸灾害及防护教育部重点实验室,南京210098 [2]江苏省海涂中心,南京210013

出　　处：《水力发电学报》2013年第1期118-125,138,共9页Journal of Hydroelectric Engineering

基　　金：国家科技支撑计划课题(2012BAB03B01);江苏省科技支撑资助项目(BE2011812)

摘　　要：基于无结构网格海洋模型(FVCOM),建立了瓯江口三维潮流和盐度数学模型。模型水平方向采用三角形网格,使得能够更好地拟合瓯江口外众多岛屿和复杂曲折的不规则岸线边界,垂向采用σ坐标。模型计算结果与实测结果吻合良好,较好地模拟了瓯江口潮流场和盐度场的时空分布。水平潮流以往复流为主,流速受地形影响,瓯江口附近海域的Euler余流表层流向外海,在峡道和岛周围内余流速较大。瓯江河口和乐清湾的水动力交换主要受潮流驱动,河口附近的盐度在垂线分布上呈部分混合型。A three-dimensional tidal flow and salinity model in the frame of an unstructured grid ocean model （FVCOM） was developed for the Oujiang River estuary. To better fit the numerous islands outside this estuary and the complex irregular coastline boundary, triangular elements was adopted for the horizontal plane and σ- coordinate in the vertical direction. The results reveal that the simulations agree well with the observed data, and they well describe the spatial and temporal variations of the tidal flow and salinity in the estuary. Most horizontal currents take the form of reversing flow, and the velocities are influenced by the terrain. The Euler residual currents near the surface tend to flow downstream toward the river, and become strong around the islands and in the deep channels, but weaken eastward to the estuary. The strength increasing of the residual currents reflects some important local features of these areas： tidal asymmetries, ebb dominance, great water depth and strong tidal currents intensity. Near the estuary outlet, the vertical salinity profiles take partially- mixing type, and the hydrodynamic exchange between the estuary and the Leqing bay is primarily driven by tidal current.

关 键 词：河流与海岸动力学 三维水动力模型 瓯江河口 有限体积 盐度 

分 类 号：P731[天文地球—海洋科学]