双层局部开孔板沉箱对波浪反射的理论研究

Theoretical analysis of the wave reflection by caissons with double-layered perforated wall

提出了一种用于研究由双层开孔板和一个不透水后板的开孔结构对斜向波反射率的理论分析方法。整个流域被分成三个子域,在每个子域内应用特征函数展开法以得到该域内包含未知展开系数的势函数的表达式,在速度势的展开中,考虑了非传播模态波浪的影响。通过匹配开孔板处的边界条件可以求解待定的展开系数,继而求解双层开孔板防波堤结构对斜向波的反射率。数值计算结果与试验结果进行了比较,符合较好。并进一步讨论了几个重要因素对反射系数的影响。

An analytical method has been proposed to deal with the reflection of oblique incident waves by breakwaters that consist of a double-layered perforated wall and an impermeable back wall. The fluid domain is divided into three sub-domains and an eigenfunction expansion method is applied in each of the domains. In the eigen-expansion of the velocity potential, evanescent waves are also included. By matching the porous boundary conditions, all the expansion coefficients can be obtained and the reflection coefficient can be solved. Numerical results of the present model are compared with experimental data. The major factors that affect the reflection coefficient are examined.