摘要
This study examines the hydrodynamic performance of short-crested wave interaction with a new porous cylindrical structure by using the scaled boundary finite element method(SBFEM),which is a semi-analytical technique combining the advantages of the finite element method and the boundary element method and with its own special features as well.The cylindrical structure consists of dual arc-shaped porous outer cylinders circumscribing an impermeable inner cylinder.A central feature of the newly extended method is that two virtual outer cylinders extending the arc-shaped porous outer cylinders with the same centre are introduced and variable porous-effect parameters are also introduced for the two virtual cylinders,so that the final SBFEM equation still can be handled in a closed-form analytical manner in the radial direction and by a finite element approximation in the circumferential direction.The entire computational domain is divided into two bounded and one unbounded domains,and a variational principle formulation is used to derive the SBFEM equation in each sub-domain.The velocity potential in bounded and unbounded domains is formulated using sets of Bessel and Hankel functions respectively,and the unknown coefficients are determined from the matching conditions.The results of numerical verification show that the approach discretises only the outermost virtual cylinder with surface finite-elements and fewer elements are required to obtain very accurate results.Influences of the incident wave parameters and structural configurations on the hydrodynamics are examined.
This study examines the hydrodynamic performance of short-crested wave interaction with a new porous cylindrical structure by using the scaled boundary finite element method (SBFEM), which is a semi-analytical technique combining the advantages of the finite element method and the boundary element method and with its own special features as well. The cylindrical structure consists of dual arc-shaped porous outer cylinders circumscribing an impermeable inner cylinder. A central feature of the newly extended method is that two virtual outer cylinders extending the arc-shaped porous outer cylinders with the same centre are introduced and variable porous-effect parameters are also introduced for the two virtual cylinders, so that the final SBFEM quation still can be handled in a closed-form analytical manner in the radial direction and by a finite element approximation in the circumferential direction. The entire computational domain is divided into two bounded and one unbounded domains, and a variational principle formulation is used to derive the SBFEM equation in each sub-domain. The velocity potential in bounded and unbounded domains is formulated using sets of Bessel and Hankel functions respectively, and the unknown coefficients are determined from the matching conditions. The results of numerical verification show that the approach discretises only the outermost virtual cylinder with surface finite-elements and fewer elements are required to obtain very accurate results.Influences of the incident wave parameters and structural configurations on the hydrodynamics are examined.
基金
supported by the National Natural Science Foundation of China (Grant Nos. 51121005 and 51138001)
the China-Germany Joint Research Project (Grant No. GZ566)
关键词
圆柱形结构
水动力性能
双圆弧
多孔
比例边界有限元法
外壁
解析技术
有限元素
scaled boundary finite element method
short-crested wave
wave diffraction
dual arc-shaped porous walls
wave-structure interaction
cylinder