贝宁海滩上波浪传播演变特性研究  

Study on wave propagation and evolution characteristics over a beach in Benin

作　　者：王广生 童林龙 罗梦岩[2,3] 张继生 WANG Guangsheng;TONG Linlong;LUO Mengyan;ZHANG Jisheng(China Harbor Engineering Company Limited,Beijing 100027,China;Key Laboratory of Ministry of Education for Coastal Disaster and Protection,Hohai University,Nanjing 210098,China;College of Harbor,Coastal and Offshore Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]中国港湾工程有限责任公司,北京100027 [2]河海大学海岸灾害及防护教育部重点实验室,江苏南京210098 [3]河海大学港口海岸与近海工程学院,江苏南京210098

出　　处：《河海大学学报（自然科学版）》2023年第6期123-129,共7页Journal of Hohai University(Natural Sciences)

摘　　要：为分析贝宁海滩上波浪传播演变特性,基于开源波浪数值计算软件COBRAS建立了贝宁典型海滩剖面数值模型,模型中采用k-epsilon紊流模型求解雷诺应力,采用流体体积法捕捉自由液面,并采用斜坡上波浪破碎试验结果对数值模型进行了验证。基于该模型对常浪条件和极端波浪条件下海滩上波浪传播规律的模拟结果表明:常浪条件下波浪主要在沙坝附近发生破碎,极端波浪条件下波浪在沙坝外侧200 m处开始发生破碎;破碎区域内水质点速度较大,常浪条件下沙坝周围的流速可达7.5 m/s,极端波浪条件下破波带内水质点速度可达12.4 m/s,且波浪回流与入射波浪在沙坝周围相互作用会形成较强的涡旋;随着波浪非线性的增强,波浪爬高也逐渐增大,在极端波浪条件下,沙丘上会发生越浪。Based on a open-source numerical software of wave,COBRAS,a two-dimensional numerical model is developed to study the wave propagation and evolution characteristics over a beach in Benin,in which the free surface is captured by the Volume-of-Fluid method and the Reynold stress is obtained by solving the k-epsilon equations.The numerical model is validated with the experimental data for the free surface of a solitary wave during the shoaling and breaking over a slope.The proposed model is then used to study the shoaling and breaking processes under ordinary and extreme wave conditions.The results show that the waves break near the sandbar under the ordinary wave condition.However,under the extreme wave condition,they start to break 200 m away from the sandbar,and during the interaction of the rundown water and the incident wave,vortexes shall be formed over the sandbar.In the breaking zone,the water velocity is relatively large,which can be 7.5 m/s under the ordinary wave condition and even reach 12.4 m/s under the extreme wave condition.With the increase of the nonlinearity of the incident wave,the runup height increases,and overtopping occurs under the extreme wave condition.

关 键 词：波浪 浅水变形 波浪破碎 流体体积法 雷诺平均的纳维-斯托克斯方程 贝宁海滩 

分 类 号：TV139.2[水利工程—水力学及河流动力学] P731.22[天文地球—海洋科学]