| 摘要: |
| 采用“σ坐标下的三维数值模式”来模拟杭州湾三维潮波运动,水平方向上以较小尺度的差分网格覆盖计算区,垂直方向上给予均匀的分层,对占本湾水位谱总能量80％的半日潮波M2和半日潮波m1((K1+O1)/2）两类进行了数值模拟。水平流动和潮位的计算结果与相应的实测值拟合良好。计算表明,水平潮流具有明显的往复流性质,主要呈东-西方向;流速自湾口向湾顶增加, M2分潮流最大可达270 cm/s左右, m1分潮流最大可达24 cm/s左右。在太阴时1和13时,于湾的中部偏南存在一个弱的逆时针向的大涡旋;在7和19时于上述位置存在一个弱的顺时针向的大涡旋。垂直流速振幅一般为10×10-2—2×10-2 cm/s,最大可达2.5×10-2 cm/s,位于乍浦附近的底层水域中。 |
| 关键词: 数值模拟 σ-坐标 潮汐 潮流 垂直涡动混合 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目,4850102 D061号 |
|
| 3D NUMERICAL SIMULATION OF TIDAL WAVES IN HANGZHOU BAY |
|
Li Shenduo1, Gu Simei2
|
|
1.Institute of Estuarine and Coastal Research, East China Normal University, Shanghai 200062;2.Shanghai Jiao Tong University, 200030
|
| Abstract: |
| The movement of tidal waves in the Hangzhou Bay is simulated by using a 3-dimensional numerical model of the barotropic ocean hydrodynamics. In order to have the same number for the vertical dividing layers in the computational rigon, the σ-coordinate, and staggered scheme in time and space, were adoped. The terms of vertical viscosity eddy are determined implicitly. In Hangzhou Bay the main tidal waves-semidiurnal constituent M2 and diurnal constituents m1((K1+O1)/2), which account for over 80 per cent of the total energy in the level spectrum, are dominant. Their amplitudes of the tide and velocity of the tidal current are about 2.5 m, 0.37 m and 2.7 m/s, 0.24 m/s respectively. Topography and water depth have obvious influence on the current field. The orientation of the maximum velocity of the M2 constituent of tidal current coincides basically with the trend of the bay topography. The velocity of the tidal current increases gradually from the east to the west. The characteristic of the rectilinear current is very strong. The ellipficity of the M2 constituent of tidal current is about ±0.01-0.1. The maximum velocity reduces downwards about 5 cm/s per meter. The average amplitude of the vertical tidal current is about 0.01-0.02 cm/s and its maximum velocity can reach about 0.25 cm/s. The harmonic constants of the tide and tidal current can be obtained from the calculated results in the paper. |
| Key words: Numerical simulation, σ-Coordinate, Tide, Tidal current, Vertical coefficient mixing |
