潜堤上波浪传播过程数值研究

摘要

In this study,a computational model is established for solving wave propagation over a submerged dike based on RANS equations combined with Level-Set method.The fifth-order finite difference WENO scheme is used for spatial discretization,and a TVD third-order Runge-Kutta explicit time scheme is employed for time discretization in the model.The Level-Set method is used for tracking the free interface between the air and water phases,and a relaxation method is employed for wave generation and absorption.In order to validate the accuracy and applicability of the model,numerical investigation of the wave propagation over a submerged dike is conducted.The numerical results show a good agreement with experimental data.Further studies are carried out to investigate the influence of physical parameters,such as wave height,submerged depth,seaward and leeward slope gradients,on the process of wave propagation over a submerged dike.Results reveal that when the wave height is higher,submerged depth smaller,and seaward slope flatter,the effect of shoaling is more obvious;when leeward slope is flatter,the effect of shoaling on wave is slightly larger,but not obvious.%以RANS方程结合Level-Set方法为研究基础,采用五阶.WENO有限差分格式进行空间离散、三阶TVDRunge-Kutta格式进行时间推进、Level-Set方法追踪波浪与空气间自由面以及解析松弛法来实现数值水槽中的造波消波,建立了一种求解潜堤上波浪传播问题的数值计算模型.选取经典的潜堤上波浪传播物理试验模型对数值模型进行了验证,水位计算结果与试验值吻合较好.进一步研究了波高、潜堤顶部淹没深度以及潜堤坡度等参数对潜堤上波浪传播过程的影响.结果表明:波高越高、淹没深度越浅、潜堤向波坡度越小,波浪受浅水作用越明显;潜堤背波坡度越小,波浪受反浅水作用稍大,但并不明显.