珊瑚岸礁孤立波爬坡特性及影响因素的数值模拟研究

Tsunami, which is similar to the solitary wave, is a kind of disastrous wave and greatly threatens the coastal life and property through the runup process. The protective capability of coral fringing reefs against the tsunami has attracted people’s attention. However, the effects of various factors associated with reef morphological and hydrodynamic parameters on the tsunami-like solitary wave runup is still unclear so far. In this research, a fully nonlinear shock-capturing Boussinesq wave model will first be implemented with improved numerical method to simulate the solitary wave characteristics over fringing reefs. Laboratory experiments will be performed to validate the effectiveness of the numerical model in predicting the solitary wave transformation, runup height and nearshore velocity. In order to clarify the influencing factors of solitary wave runup over fringing reefs, parametric study will then be conducted using the validated model to study the effects of reef morphological and hydrodynamic parameters on the wave runup height and nearshore velocity comprehensively. The results of this study will provide valuable reference for the activities of disaster reduction, engineering design and reef reconstruction over the fringing reefs.

海啸波近似于孤立波，是一种灾害性海浪，通过近岸爬坡过程严重威胁沿海地区生命及财产安全。珊瑚岸礁因其特殊的地形地貌在抵御海啸等海洋灾害中的作用受到了人们的关注，但目前有关岸礁地形和水动力因素对海啸孤立波爬坡特性的影响仍不甚明了。本项目首先基于完全非线性Boussinesq方程，改进数值解法，采用激波捕捉法处理波浪破碎，建立孤立波与岸礁地形相互作用的数值计算模型，并开展模型在模拟孤立波波面、爬高和内部流速变化的验证工作。然后利用验证后的模型，进行孤立波爬坡特性的参数化研究，深入了解岸礁各地形和水动力因素对孤立波爬高和近岸流速的影响规律和影响机理，阐明珊瑚岸礁孤立波爬坡的影响因素。本项目的研究成果将为岸礁海域的防灾减灾、工程设计以及珊瑚礁改造等活动提供借鉴意义。

珊瑚岸礁因其特殊的地形地貌被认为是抵御波浪灾害的天然屏障，但现场调查显示珊瑚岸礁对于海啸、台风浪等灾害的防御作用不一，而波浪爬坡是波浪侵袭近岸的主要过程。本项目以数值模拟为主，物理模型实验为辅，自主研发了岸礁波浪传播及爬坡定量分析的数学模型，通过物理模型实验获取了岸礁波浪爬坡的实测数据，验证了模型的准确性，并基于项目开发的模型对岸礁海岸波浪爬坡特性及其影响因素开展了系统研究，阐明了孤立波爬坡高度及最大动量通量、不规则波爬坡高度对岸礁地形和水动力参数的响应规律和机制，揭示了岛屿裙礁周围孤立波的典型传播过程，阐明了岛屿裙礁周围孤立波传播过程及爬坡分布对岸礁地形和水动力参数的响应规律和机制。研究成果可为岸礁海域的防灾减灾、工程设计规划等提供借鉴。依托本项目资助，项目负责人以通讯作者或第一作者发表标注本基金的各类学术论文8篇，其中SCI收录论文7篇，中文核心论文1篇，获得发明专利授权1项，毕业硕士研究生3人，获中国航海学会科学技术奖一等奖1项(排名3)。