波浪与外圆弧开孔壁双圆筒柱的相互作用

应用比例边界有限元法(SBFEM)研究了短峰波与圆筒外接圆弧开孔结构物的相互作用. 求解时将外接圆弧延伸构建一个虚拟圆, 该圆的孔隙影响系数可由矩阵G_0统一进行表达. 整个流场可划分成一个有限域和一个无限域. SBFEM只需对虚拟圆边界进行离散, 使空间维数降低一阶, 在圆的半径方向保持解析, 并且无限域处的辐射边界条件能自动满足. 利用变分原理推导SBFEM方程, 有限域和无限域分别采用贝塞尔函数和汉克尔函数作为基函数来求得对应域的解. 将计算结果与解析解和其他数值方法进行了比较, 验证了该方法是一种用很少单元便能得到精确结果的高效算法. 进一步研究了诸如短峰波波向、结构的几何、材料参数等因素对结构所受波浪载荷及绕射波轮廓的影响, 并进行了分析. 

WAVE INTERACTION WITH DOUBLE-CYLINDER STRUCTURER WITH ARC-SHAPED POROUS OUTER WALL

The scaled boundary finite element method（SBFEM） is applied to solve the problem of hydrodynamic interaction between the short-crested wave and the circular cylinder circumscribed arc-shaped porous structure.The porous arc is extended to form an imaginary circular cylindrical interface.As a result,the entire computational domain is divided into one bounded domain and one unbounded domain.The porous coefficient of the whole imaginary circular interface is represented by a diagonal matrix G₀.Analytical procedure is applied in the reduced direction,and only the boundary of the exterior cylinder needs be discretized to reduce spatial dimension by one.In addition,the present approach can meet the boundary condition at the infinity automatically.Hankel and Bessel functions are chosen as the basis functions for the solution SBFEM equations. Comparisons are made between the results solved by SBFEM and those by acquired analytical solution or solutions by other methods in the literature.The results show that the proposed approach yields excellent results with quite few discretized nodes and quick convergence.The influence of varying wave parameters and structure configuration on the system hydrodynamics is extensively examined.These research results are of practical significance to the hydrodynamic analysis and design for the circular cylinder circumscribed arc-shaped porous structure.