关键词: 海上浮式风力机, 流固耦合, 干扰抑制, 龙格-库塔法, 波纹柱体

Abstract: In order to mitigate the fatigue damage of the riser and mooring system by vortex-induced motion（VIM）, in the present work, a numerical simulation for the characteristics of VIM and suppression mechanism of a new wavy cylindrical structure is proposed. The nonlinear coupling interaction between the structure and fluid is performed by user-defined function （UDF） and dynamic mesh techniques,and the differential equations of motion are solved by the fourth-order Runge-Kutta methods. It was found that the VIM characteristics of the wavy cylinders and cylinder were significantly different. The cylinder shows a significant lock-in characteristic with the increasing reduced velocity,while the response characteristic of the wavy cylinders are related to the wave height Hw/D. The lock-in phenomenon also occurs when the wave height is Hw/D=0.01 and 0.05,but the lock-in region is smaller than that of circular cylinder,and the lock-in problem is no longer occurs when the wavy height is Hw/D=0.02-0.04. The results show that the wavy cylinders have a significant suppression effect on the VIM.

Key words: offshore wind turbines, fluid structure interaction, interference suppression, Runge Kutta method, wavy cylinders