完全非线性波浪与二维固定结构物作用的IGN-BEM耦合分析模型  

A coupled IGN-BEM model for the interaction between fully nonlinear waves and 2D fixed bodies

作　　者：苏高飞 勾莹 滕斌[1] SU Gaofei;GOU Ying;TENG Bin(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《海洋工程》2023年第3期1-13,共13页The Ocean Engineering

基　　金：国家重点研发计划资助项目(2021YFB2601100)。

摘　　要：为高效准确地对完全非线性波浪与二维固定结构物的相互作用进行模拟分析,建立了二维完全非线性时域耦合模型。耦合模型将计算域划分为靠近结构物的内域和远离结构物的外域,每个区域均采用满足完全非线性自由水面边界条件的波浪模型进行求解。在内域使用Laplace方程描述流体运动并采用高阶边界元法(BEM)对其进行求解;而在没有结构物的外域,波浪运动的控制方程为Irrotational Green-Naghdi(IGN)方程并采用有限元法(FEM)对其进行求解。内域和外域通过一段重叠区域进行耦合,从而实现模型间变量的传递。首先利用耦合模型分别对规则波的传播、直墙前立波的生成以及相关物理模型试验进行模拟,数值结果与精确解和试验结果的良好吻合验证了耦合模型耦合方式的合理性以及处理非线性问题的准确性;然后使用耦合模型模拟分析了波浪与固定结构物间的相互作用,并将结果与线性解析解以及完全非线性BEM模型的结果进行了对比分析,进一步证明了耦合模型的正确性与高效性。In order to simulate and analyze the interaction between fully nonlinear waves and two-dimensional fixed structures efficiently and accurately,a two-dimensional fully nonlinear time-domain coupled model is established.The coupled model divides the calculation domain into an inner domain close to the structure and an outer domain far away from the structure.The fully nonlinear free surface boundary conditions are used in each sub-domain.Laplace equation is used to describe the fluid motion in the inner domain and solved by the higher-order boundary element method(BEM),while the governing equation of wave motion in the outer domain without structure is Irrotational Green-Naghdi(IGN)equation and is solved by the finite element method(FEM).The inner domain and outer domain are coupled through an overlapping region.Firstly,the coupled model is used to simulate the propagation of regular waves,the generation of standing waves in front of a vertical wall and the relevant physical experiment.The numerical results are in good agreement with the theoretical results and the experimental data,which verifies the rationality and accuracy of the coupled model.Then the coupled model is used to simulate and analyze the interaction between waves and fixed structures,and the results are compared with the linear analytic solutions and the results of a fully nonlinear BEM model,which further proves the correctness and efficiency of the coupled model.

关 键 词：IGN模型 BEM模型 模型耦合 完全非线性 数值波浪水槽 规则波传播 立波模拟 

分 类 号：P751[交通运输工程—港口、海岸及近海工程] TV139.2[天文地球—海洋科学]