| 摘要: |
| 建立了一个太湖梅梁湾三线水动力学模型，模拟了框架湾的水平及垂直流场分布。结果表明：（1）表面流场与风向一致，而底层流场与表面流场的方向完全相反，表现为很明显的补偿流；（2）水平流速基本上自表层向下递减，过渡层的流速比表层和底层小；（3）在风场的作用下可产生垂直环流系统，其中在东南风的作用下产生逆时针的垂直环流（由南向北看），而在西北风的作用下产生顺时针垂直环流；（4）垂直速度自岸边向湖中心递减，其量级远小于水平流速。 |
| 关键词: 垂直环流 补偿流 风生流 跳点法 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目，39500027号;江苏省社会发展研究基金资助项目，BS95035号 |
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| STUDIES ON A THREE-DIMENSIONAL HYDRO-DYNAMIC MODEL FOR MEILIANG BAY, TAIHU LAKE I. MODEL DESCRIPTION AND RESULT INTERPRETATION |
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ZHU Yong-chun,CAI Qi-ming
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Nanjing Institute of Geography and Limnology The Chinese Academy of Sciences, Nanjing, 210008
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| Abstract: |
| In a three-dimensional model of wind-driven currents in Meiliang Bay of Taihu Lake developed in this study, the water mass is divided into five layers vertically and the leap-frog method is used. The model is used to simulate the horizontal and vertical currents in Meiliang Bay. The currents are computed from the following equations:
where u, v, w are currents for x, y, z directions, respectively, p is water pressure, ρ is water density, g is acceleration of gravity, Ah, Av are horizontal and vertical diffusion coefficients.
After a constant southeasterly wind blows for 30 hours, the surface layer flow field accords with the wind direction, but the near lake bottom flow opposes that of the surface flow and shows characteristics of compensation flow. In addition, there exist vertical currents in the lake under the lasting action of wind. Looking from south toward north, a counterclockwise circulation is formed in the vertical profile in response to southeasterly wind and a clockwise circulation is formed in association with northwesterly winds. The results also show that the absolute horizontal flow velocity decreases from the surface to the bottom, whilst the absolute vertical flow velocity decreases from the shoreline to the center of the lake. |
| Key words: Vertical current, Compensation flow, Wind-driven current, Leap-frog method |
