| 摘要: |
| 利用2013年夏季包括大、中、小潮的三门湾大范围、同步水文观测资料，系统分析了三门湾近期潮动力的时空变化特征.结果表明，三门湾属于强潮海湾，湾顶处的各项潮汐特征值均大于湾口处.潮汐属于正规半日潮性质，潮波在向湾顶传播过程中浅水分潮增强明显.涨、落潮流历时相当，涨、落潮平均流速大小也比较接近，整体上优势流保持在45%～58%之间，涨落潮动力相对平衡.涨、落潮流矢表现出明显的往复流运动形式，整体涨落潮流向顺应三门湾的平面形态，主流向与湾内等深线基本平行.底摩擦对潮流的垂向结构作用明显，流速在垂向方向存在着明显的差异，大致成对数型结构分布，即表层或次表层流速最大，越靠下层流速越小，底层流速最小.各个测站之间，底层流速相对集中，越靠上层各测站之间流速大小差异越大，表层和次表层各站点之间流速大小差异最大.流速梯度极大值出现在急流附近，流速梯度的极小值出现在憩流附近.海床底部的粗糙度对流速梯度有着较大的影响. |
| 关键词: 海洋水文学 三门湾 潮动力特性 流速梯度 垂向变化 |
| DOI：10.3969/J.ISSN.2095-4972.2017.02.015 |
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| 基金项目:国家自然科学基金青年基金资助项目(41506103)；浙江省自然科学基金青年基金资助项目（LQ16D060007） |
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| Field observation and analysis on the characteristics of tidal dynamics in Sanmen Bay |
| SONG Ze-kun,SHI Wei-yong,ZHANG Feng,WU Qing-song,YANG Bin,ZHOU Yang,YANG Zhong-yong |
| (Key Laboratory of Engineering Oceanography， Second Institute of Oceanography， SOA， Hangzhou 300012， China;College of Hydraulic and Environmental Engineering， China Three Gorges University， Yichang 443002， China) |
| Abstract: |
| In this paper， the characteristics of tidal dynamics in Sanmen Bay have been analyzed on water current observations in 2013. The result shows that Sanmen Bay is a strong tidal bay where the tidal is higher in top of the bay than the bay mouth. The tidal property belongs to regular semidiurnal tide and the amplitude of shallow water constituents comes to stronger toward the top of the bay. The flood/ebb time duration is similar and the flood/ebb current velocities are similar， too. The dominant current is between 45%～58%. Flow vector is parallel to the coastal line in the rectilinear current movement， and the bottom friction has significant effects on the vertical structure of tidal current. The flow rate in vertical direction is different remarkably and distributes logarithmically. It is the maximum in the surface or subsurface water and decreases toward the bottom with minimized value in the underlying water. At all the stations， the underlying flow rate is relatively concentrated. The more upper the layer， the more differences in the flow rate at all the stations. The largest velocity gradient appears in the time of rapid flow and the smallest velocity gradient appears in the time of slack water. Roughness of the sea bed at the bottom has great impact on the velocity gradient． |
| Key words: marine hydrography Sanmen Bay tidal dynamic character velocity gradient vertical variation |
