岸礁地形上波浪破碎的试验与模拟研究  

Experimental and Numerical Study of Wave-breaking on Reef Flat

作　　者：王秭霖 张弛[1] 李元 陈松贵 陈树彬 迟善航 隋倜倜 王岗[2] Wang Zilin;Zhang Chi;Li Yuan;Chen Songgui;Chen Shubin;Chi Shanhang;Sui Titi;Wang Gang(The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210024,China;Key Laboratory of Coastal Disaster and Protection,Ministry of Education,Hohai University,Nanjing 210024,China;Tianjin Research Institute for Water Transport Engineering,Tianjin 300456,China)

机构地区：[1]河海大学水灾害防御全国重点实验室,南京210024 [2]河海大学海岸灾害及防护教育部重点实验室,南京210024 [3]交通运输部天津水运工程科学研究院,天津300456

出　　处：《水动力学研究与进展（A辑）》2024年第3期372-381,共10页Chinese Journal of Hydrodynamics

基　　金：国家重点研发计划项目(2022YFC3102302)。

摘　　要：珊瑚礁可以消散波能并保护海岸线,具有十分重要的生态和经济价值。深入认识波浪破碎能量耗散在礁坪上的分布规律,对研究岸礁地形上的泥沙运动或涉水建筑物工程响应等问题具有积极意义。该文在实验室水槽中开展了岸礁地形上波浪破碎试验,分析了礁坪水深、入射波高和谱峰周期对波浪和增减水演化的影响规律。采用基于能量守恒的波相平均波浪数值模型对沿程波高和增减水进行了模拟计算,并根据模型计算结果分析了礁坪上波浪破碎能量耗散沿程分布均匀程度与入射波要素、礁坪水深的定量关系。结果表明:在礁缘处经历剧烈破碎后,波高(波浪增水)在礁坪上趋于稳定,稳定值与礁坪水深呈正(负)相关;波相平均数值模型能准确模拟珊瑚礁上方波高和增减水的沿程变化趋势,均方根误差分别为0.0033 m和0.0013 m;引入无量纲参数波能熵表征波浪破碎能量耗散在礁坪上分布的均匀程度,发现在一定范围内,破波耗能在礁坪上分布的均匀程度与礁坪水深、入射波周期呈正相关,与入射波高呈负相关;建立基于入射波要素和礁坪水深的波能熵参数化预测公式,得出相关性系数的平方R2=0.85。Coral reefs have the functions of dissipating wave energy and protecting the coastline,which have very important ecological and economic values.An in-depth understanding of distribution patterns of wave energy dissipation due to wave-breaking on reef flat is critical for the analysis of sediment transport and the response of coastal structures in shore-reef topography.In this study,wave-breaking on the shore-reef topography experiments are conducted in a wave flume to examine the effects of submerged depth of reef flat,incident wave height and spectral peak period on wave and wave-setup evolution.A phase-averaged numerical model based on energy conservation is employed to simulate wave heights and wave-setup,and the calculated data are used to analyze the relationship between the distribution of wave energy dissipation due to wave-breaking and incident wave elements and submerged depth of reef flat.The results indicate that wave heights tend to stabilize on the reef flat after breaking violently near the reef edge,and the stable wave heights(wave-setup)correlate positively(negatively)with submerged depth of reef flat.The numerical model accurately predicted wave heights and wave-setup along the coral reef,and the Root Mean Square Errors are 0.0033 m and 0.0013 m respectively.A dimensionless parameter,wave entropy,is introduced to characterize the uniformity of the distribution of wave energy dissipation,and it is found that within a certain range,the uniformity of the distribution of the wave energy dissipation due to wave-breaking is positively correlated with the submerged depth of reef flat and the incident wave period,and negatively correlated with the wave height.Taking incident wave elements and submerged depth of reef flat into account in this paper,then a parameterized formula to predict wave entropy is proposed,and the square of correlated coefficient is 0.85.

关 键 词：珊瑚礁 波浪破碎 波能耗散 波能熵 

分 类 号：P753[交通运输工程—港口、海岸及近海工程]