| 摘要: |
| 通过水槽实验对规则波浪作用下珊瑚岸礁上沿礁分布的水位和流速进行了详细的测量,研究岸礁破碎带附近的波浪演化和波生流特性。在典型卷破波条件下测试了礁冠存在与不存在的两种情况。实验结果表明：由于多重波浪反射作用引起岸礁上形成不完全驻波,而破碎带附近的浅化作用则产生高次谐波,波浪破碎所耗散的波能主要来源于主频波,礁坪上透射波成分中二次谐波与主频波的能量相当；礁冠的存在引起破碎带宽度减小、礁坪上增水变大以及礁坪上各次谐波变小；礁冠不存在时岸礁上波生流的沿礁分布与平直海岸相似,而礁冠的存在一定程度上阻碍了礁坪上水体向外海的回流。 |
| 关键词: 高次谐波 波生流 破碎带 珊瑚岸礁 |
| DOI：10.11759/hykx20160313001 |
| 分类号:TV139.2 |
| 基金项目:国家自然科学基金资助项目(51309035, 51239001)；水文水资源与水利工程科学国家重点实验室开放研究基金 (2014491011)；高等学校博士学科点科研基金新教师类(20134316120004)；长沙理工大学研究生科研资助项目(CX2015SS07)。 |
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| Experimental Study of Wave Transformation and Wave-driven Current around the Surf Zone over Coral Reefs |
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YAO Yu,TANG Zheng-jiang,DU Rui-chao and JIANG Chang-bo
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School of Hydraulic Engineering,Changsha University of Science and Technology;China;Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province;China,School of Hydraulic Engineering,Changsha University of Science and Technology,School of Hydraulic Engineering,Changsha University of Science and Technology,School of Hydraulic Engineering,Changsha University of Science and Technology
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| Abstract: |
| To investigate the wave transformation and wave-driven current around the surf zone over fringing reefs, a series of laboratory experiments are performed in a wave flume to measure the cross-reef water lever and flow in details. Experimental results are reported for two reef profiles with and without the reef crest under a typical plunging breaker condition. Data analysis shows that partial standing waves across the reef are formed due to multiple wave reflection, and higher harmonics around the surf zone are generated through wave shoaling. The energy dispassion due to wave breaking results primarily from the fundamental harmonics, and the second harmonic waves become comparable to the fundamental harmonics on the reef flat. The presence of reef crest reduces the surf zone width as well as increases the wave-induced setup, and it also decreases the harmonic wave amplitudes on the reef flat. The variation of wave-driven current across fringing reef without the reef crest is similar to that for plane beaches. The existence of reef crest causes retention of the mean flow shoreward of crest to some extent. |
| Key words: higher harmonic waves wave-driven current surf zone fringing reef |