Experimental study on the influence of permeable trapezoidal reef on the hydrodynamic characteristics of solitary wave complex reefs
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摘要: 珊瑚岛礁地貌作为海岸的天然屏障,近年来由于人类活动的影响产生了不可逆的破坏。失去天然屏障的岛屿如何抵抗极端波浪的侵蚀成为了迫在眉睫的问题。本文基于波浪水槽物理模型试验,从入射波高、礁坪水深、孔隙半径等参数展开对复杂珊瑚岛礁地形附近的孤立波水动力特性研究,并从能量的角度揭示人工礁体的消波机理。试验结果表明:透空式梯形礁体能够对波浪能具有削弱作用,并加快波浪破碎;受礁体的影响波浪在通过礁体后发生局部减水,且可以降低后续在礁坪上传播的有效水深;透射系数和反射系数均随入射波高的增大而增大;随礁坪水深的增大反射系数减小,透射系数增大;反射系数随孔隙半径的增大而减小,透射系数无明显规律。透空式梯形礁体可以有效降低波浪的透射强度,实现对岛屿的防护,并且透空式梯形礁体在削弱波浪能量的同时还可以兼顾生态友好、减少结构物受力、为水体交换提供空间。Abstract: As a natural barrier to the coast, coral reefs have caused irreversible damage in recent years due to the influence of human activities. How to resist the erosion of extreme waves has become an urgent problem for islands that have lost their natural barriers. Based on the physical model test of wave flume, this paper studies the complex hydrodynamic characteristics of solitary waves near coral reef topography from the parameters of incident wave height, reef flat water depth and pore radius, and reveals the wave dissipation mechanism of artificial reefs from the perspective of energy. The test results show that the permeable artificial reef can significantly weaken the wave energy, and the ability of the artificial reef group to weaken the wave energy has a certain limit. Under the influence of the reef, the wave is partially reduced after passing through the reef, and the effective water depth of the subsequent propagation on the reef flat can be reduced. The transmission coefficient and reflection coefficient increase with the increase of incident wave height. With the increase of reef flat water depth, the reflection coefficient decreases and the transmission coefficient increases. The reflection coefficient decreases with the increase of pore radius, and the transmission coefficient has no obvious law. The permeable trapezoidal reef can effectively reduce the transmission intensity of waves and realize the protection of islands. The permeable trapezoidal reef can not only weaken the wave energy, but also take into account the ecological friendliness, reduce the force of structures and provide space for water exchange.
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Key words:
- solitary wave /
- artificial reef /
- hydrodynamic characteristics /
- physical experiment /
- wave energy
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图 11 有无礁体地形在不同礁坪水深下透射系数(CT)和反射系数(CR)变化
●、○表示有礁体地形的反射系数和透射系数;◆、◇表示无礁体地形的反射系数和透射系数
Fig. 11 Changes of transmission coefficient (CT) and reflection coefficient (CR) of reef or non-reef terrain under different reef flat water depths
●, ○Represents the transmission coefficient and reflection coefficient with reef terrain;◆, ◇Reflection the transmission coefficients and reflection coefficient of non-reefs terrain
表 1 测点位置
Tab. 1 Position of measuring points
测点编号 WG1 WG2 WG3 WG4 WG5 WG6 WG7 WG8 WG9 测点位置/m 12.52 13.121 13.679 23.23 23.515 23.8 24.085 24.37 24.655 测点编号 WG10 WG11 WG12 WG13 WG14 WG15 WG16 WG17 WG18 测点位置/m 25.33 25.845 26.34 26.9 27.461 28.02 28.582 29.14 29.7 表 2 试验工况设置
Tab. 2 Experimental condition setting
工况 hr/m H/m 地形类型 r/m A1 0 0.06 无礁体 0 A2 0.025 0.04 无礁体 0 A3 0.025 0.06 无礁体 0 A4 0.025 0.08 无礁体 0 A5 0.025 0.1 无礁体 0 A6 0.05 0.06 无礁体 0 A7 0.075 0.06 无礁体 0 B1 0 0.06 梯形礁体 0.0075 B2 0.025 0.04 梯形礁体 0.005 B3 0.025 0.06 梯形礁体 0.005 B4 0.025 0.08 梯形礁体 0.005 B5 0.025 0.1 梯形礁体 0.005 B6 0.025 0.04 梯形礁体 0.0075 B7 0.025 0.06 梯形礁体 0.0075 B8 0.025 0.08 梯形礁体 0.0075 B9 0.025 0.1 梯形礁体 0.0075 B10 0.025 0.04 梯形礁体 0.001 B11 0.025 0.06 梯形礁体 0.001 B12 0.025 0.08 梯形礁体 0.001 B13 0.025 0.1 梯形礁体 0.001 B14 0.05 0.06 梯形礁体 0.0075 B15 0.075 0.06 梯形礁体 0.0075 -
[1] Cho Y S, Park K Y, Lin T H. Run-up heights of nearshore tsunamis based on quadtree grid system[J]. Ocean Engineering, 2004, 31(8/9): 1093−1109. [2] Synolakis C E, Bernard E N. Tsunami science before and beyond Boxing Day 2004[J]. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2006, 364(1845): 2231−2265. doi: 10.1098/rsta.2006.1824 [3] Kubota T, Saito T, Nishida K. Global fast-traveling tsunamis driven by atmospheric Lamb waves on the 2022 Tonga eruption[J]. Science, 2022, 377(6601): 91−94. doi: 10.1126/science.abo4364 [4] Lynett P, McCann M, Zhou Zili, et al. Diverse tsunamigenesis triggered by the Hunga Tonga-Hunga Ha’apai eruption[J]. Nature, 2022, 609(7928): 728−733. doi: 10.1038/s41586-022-05170-6 [5] Ren Zhiyuan, Higuera P, Liu P L F. On tsunami waves induced by atmospheric pressure shock waves after the 2022 Hunga Tonga-Hunga Ha'apai volcano eruption[J]. Journal of Geophysical Research: Oceans, 2023, 128(4): e2022JC019166. doi: 10.1029/2022JC019166 [6] Yao Yu, He Tiancheng, Deng Zhengzhi, et al. Large eddy simulation modeling of tsunami-like solitary wave processes over fringing reefs[J]. Natural Hazards and Earth System Sciences, 2019, 19(6): 1281−1295. doi: 10.5194/nhess-19-1281-2019 [7] 姚宇, 袁万成, 杜睿超, 等. 岸礁礁冠对波浪传播变形及增水影响的实验研究[J]. 热带海洋学报, 2015, 34(6): 19−25. doi: 10.11978/2015031Yao Yu, Yuan Wancheng, Du Ruichao, et al. Experimental study of reef crest's effects on wave transformation and wave-induced setup over fringing reefs[J]. Journal of Tropical Oceanography, 2015, 34(6): 19−25. doi: 10.11978/2015031 [8] Young I R. Wave transformation over coral reefs[J]. Journal of Geophysical Research: Oceans, 1989, 94(C7): 9779−9789. doi: 10.1029/JC094iC07p09779 [9] Titov V, Rabinovich A B, Mofjeld H O, et al. The global reach of the 26 December 2004 Sumatra tsunami[J]. Science, 2005, 309(5743): 2045−2048. doi: 10.1126/science.1114576 [10] Danielsen F, Sørensen M K, Olwig M F, et al. The Asian tsunami: a protective role for coastal vegetation[J]. Science, 2005, 310(5748): 643−643. doi: 10.1126/science.1118387 [11] “中国工程科技2035发展战略研究”海洋领域课题组. 中国海洋工程科技2035发展战略研究[J]. 中国工程科学, 2017, 19(1): 108−117. doi: 10.15302/J-SSCAE-2017.01.016Task Force for the Research on China’s Engineering Science and Technology Development Strategy 2035 Marine Research Group. Development strategy for China's marine engineering science and technology to 2035[J]. Strategic Study of CAE, 2017, 19(1): 108−117. doi: 10.15302/J-SSCAE-2017.01.016 [12] Fang Kezhao, Xiao Li, Liu Zhongbo, et al. Experiment and RANS modeling of solitary wave impact on a vertical wall mounted on a reef flat[J]. Ocean Engineering, 2022, 244: 110384. doi: 10.1016/j.oceaneng.2021.110384 [13] 刘铁威, 屈科, 黄竞萱, 等. 孤立波在透水岸礁上水动力特性数值模拟研究[J]. 水动力学研究与进展, 2021, 36(2): 180−191.Liu Tiewei, Qu Ke, Huang Jingxuan, et al. Numerical investigation of hydrodynamic characteristics of solitary wave over permeable fringing reef[J]. Chinese Journal of Hydrodynamics, 2021, 36(2): 180−191. [14] Yao Yu, He Fang, Tang Zhengjiang, et al. A study of tsunami-like solitary wave transformation and run-up over fringing reefs[J]. Ocean Engineering, 2018, 149: 142−155. doi: 10.1016/j.oceaneng.2017.12.020 [15] 袁涛, 施奇佳, 姚宇, 等. 人工礁研究进展与展望[J]. 热带海洋学报, 2023, 42(1): 192−203. doi: 10.11978/2022027Yuan Tao, Shi Qijia, Yao Yu, et al. Research progresses and prospects of the artificial reefs[J]. Journal of Tropical Oceanography, 2023, 42(1): 192−203. doi: 10.11978/2022027 [16] Liu T L, Su D T. Numerical analysis of the influence of reef arrangements on artificial reef flow fields[J]. Ocean Engineering, 2013, 74: 81−89. doi: 10.1016/j.oceaneng.2013.09.006 [17] 于定勇, 王逢雨, 张彩霞, 等. 梯型台人工鱼礁体流场效应数值研究[J]. 中国海洋大学学报, 2020, 50(12): 135−143.Yu Dingyong, Wang Fengyu, Zhang Caixia, et al. Research on flow field around trapezoidal artificial reefs[J]. Periodical of Ocean University of China, 2020, 50(12): 135−143 [18] 成泽毅, 叶灿, 高宇, 等. 不同布设间距和来流速度下方型人工鱼礁上升流效应的数值模拟[J]. 海洋与湖沼, 2023, 54(3): 665−678. doi: 10.11693/hyhz20221000262Cheng Zeyi, Ye Can, Gao Yu, et al. Scheme analysis of upwelling effects in artificial reefs in different layouts[J]. Oceanologia et Limnologia Sinica, 2023, 54(3): 665−678. doi: 10.11693/hyhz20221000262 [19] Zhu Gancheng, Ren Bing, Wen Hongjie, et al. Analytical and experimental study of wave setup over permeable coral reef[J]. Applied Ocean Research, 2019, 90: 101859. doi: 10.1016/j.apor.2019.101859 [20] 刘同渝. 人工鱼礁的流态效应[J]. 水产科技, 2003(6): 43−44.Liu Tongyu. Flow pattern effect of artificial reefs[J]. Fishery Science and Technology, 2003(6): 43−44. (查阅网上资料, 未找到本条文献英文翻译, 请确认) [21] 王旭, 屈科, 门佳. 透水珊瑚岸礁亚重力波水动力特性数值研究[J]. 海洋学报, 2023, 45(9): 152−167.Wang Xu, Qu Ke, Men Jia. Numerical study on infragravity wave hydrodynamics of permeable fringing reef[J]. Haiyang Xuebao, 2023, 45(9): 152−167. [22] Neelamani S, Rajendran R. Wave interaction with T-type breakwaters[J]. Ocean Engineering, 2002, 29(2): 151−175. doi: 10.1016/S0029-8018(00)00060-3