摘要: |
本文通过实验室实验的方法,探讨了非均匀密度层结下内潮射线的生成与传播规律。利用粒子图像测速技术(PIV)对流场进行测量,并计算了内潮能通量。实验结果表明,无转折深度时,内潮射线传播至不同浮频率水层会发生折射,向上传播时有能量聚焦现象;转折深度高于地形高度时,在浮频率大于强迫频率的上层流体中仍有内潮射线生成,但能量较弱,水平通量的深度积分相对于无转折深度时更小,且地形越高越容易在上层激发内潮射线。对水平流速做经验正交函数(EOF)分解,得到的主要模态与内潮斜压模态有很好的对应性。 |
关键词: 内潮生成 非均匀密度分层 能通量 PIV技术 EOF分析 |
DOI:10.11693/hyhz20180100001 |
分类号:P731.24 |
基金项目:国家自然科学基金项目,41476001号。 |
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EXPERIMENTAL STUDY ON THE GENERATION AND PROPAGATION OF INTERNAL TIDE BEAM IN NON-UNIFORM STRATIFICATIONS |
ZHAO Meng-Xin1, CHEN Xu1, WANG Shu-Ya1, MENG Jing2
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1.Key Laboratory of Oceanography, Ocean University of China, Qingdao 266100, China;2.College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China
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Abstract: |
An experiment was conducted to investigate the generation and propagation of the internal tide in nonuniform density stratification. Particle Image Velocimetry (PIV) technology was applied to measure the velocity filed of internal tides. The results show that the internal tide beams were refracted when it spread into a stronger stratification layer in the absence of turning depth. In addition, the propagation of the internal tides changed and the energy of the internal tides was focused. When the topography was below the turning depth, the internal tide beams could also be generated in the upper layer with feebleness energy. However, the normalized depth-integrated energy flux is less than that in the first case. In the upper layer, the internal tides generated in higher topography was stronger than those in lower topography. Moreover, the EOF vertical modes resemble corresponding baroclinic modes. |
Key words: internal tide generation non-uniform stratifications energy flux PIV EOF analysis |