堤前红树林对直立堤波压力影响的数值模拟研究  

Numerical simulation on the impact of mangroves on wave pressure on vertical sea dikes

作　　者：雷佳欣 张荣[1,2] 陈永平 王远[1,2] 姚鹏 Lei Jiaxin;Zhang Rong;Chen Yongping;Wang Yuan;Yao Peng(The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210098 China;College of Harbour,Coastal and Offshore Engineering,Hohai University,Nanjing 210098 China)

机构地区：[1]河海大学水灾害防御全国重点实验室,江苏南京210098 [2]河海大学港口海岸与近海工程学院,江苏南京210098

出　　处：《海洋学报》2024年第2期117-130,共14页

基　　金：国家重点研发计划项目(2023YFC3008100)。

摘　　要：基于非静压模型SWASH,建立数值波浪水槽,通过设置有无红树林的对比实验,系统研究了波浪-红树林-直立堤相互作用时的水动力特性,并分析了波陡,相对水深,厄塞尔数,红树林长度、密度、特征直径等因素对直立堤堤前波高、迎浪面最大波压力的影响。研究结果表明:无红树林时Goda公式无法准确估算直立堤上的冲击荷载;在模型比尺为1∶10的数值实验中,2 m宽的堤前红树林可使波高衰减6%~45%,波压力衰减11%~74%,然而,在相对波高较大且红树林特征参数较小时会引起堤前波高增大4%~26%;在本文考虑的水力条件下,最大波压力随波陡减小而减小58%~93%,随相对水深增大而减小42%~72%,随厄塞尔数减小而减小87%~96%;堤前波高和波压力衰减率随红树林宽度、密度及特征直径的增加而非线性增加。研究结果可为进一步认识红树林的消浪效应及红树林生态系统与海堤组合的海岸防护工程的设计与规划提供科学的依据。Based on the non-hydrostatic model SWASH,a numerical wave flume was established to systematically investigate the hydrodynamic characteristics of the interaction between waves,mangroves,and vertical sea dikes through a comparative experiment with and without mangroves.The study analyzed the influence of factors such as wave steepness,relative water depth,Ursell number,mangrove length,density,and characteristic diameter on the wave height in front of the sea dike and the maximum wave pressure on the windward side of the sea dike.The results indicate that in the absence of mangroves,the Goda formula cannot accurately estimate the impact load on the vertical sea dike.In a numerical experiment with a model scale of 1∶10,a 2 m-wide mangrove in front of the dike was observed to reduce wave height by 6%to 45%and wave pressure by 11%to 74%.However,in conditions with relatively large wave heights and smaller characteristic parameters of the mangrove,an increase in the wave height in front of the dike by approximately 4%to 26%was noted.In the hydraulic conditions considered in this study,the maximum wave pressure decreased by 58%to 93%with a decrease in wave steepness,by 42%to 72%with an increase in relative water depth,and by 87%to 96%with a decrease in the Ursell number.The attenuation rates of wave height and wave pressure in front of the dike non-linearly increased with the increase in the width,density,and characteristic diameter of the mangroves.These findings provide a scientific basis for a deeper understanding of the wave-damping effects of mangroves,as well as for the design and planning of coastal protection projects combining mangrove ecosystems with sea dikes.

关 键 词：红树林 直立堤 波压力 数值模拟 

分 类 号：P753[交通运输工程—港口、海岸及近海工程]