Vortex-induced Vibration of Elastically Connected Multiple Circular Cylinders in a Side-by-side Arrangement in Steady Flow

• 作者: Kalyani Kaja Ming Zhao
• 来源期刊: 水利科学与海洋工程(英文)
• 学科: 物理学
• 关键词: Vortex induced vibration Multiple cylinders Numerical method
• 年，卷（期）: 2020,（1）
• 页码范围: 1-15
• 页数: 15页
• 分类号: O35

摘要

Vortex-induced vibration(VIV)of multiple circular cylinders elastically connected together in a side-by-side arrangement subject to steady flow is investigated numerically at a low Reynolds number of 150 and a mass ratio of 2.Simulations are conducted for two-,five-and ten-cylinder systems over a wide range of reduced velocities.The aim of the study is to identify the high-amplitude response range of the reduced velocity for the multiple degree of freedom vibration system and identify the difference between the responses of the single-and multiple-degree-of-freedom vibrations.Unlike the single cylinder case,distinct lock-in between the response frequency and any of the structural natural frequencies in a wide range of reduced velocity is not observed in the multiple-cylinder cases.Instead,the response frequency increases continuously with increasing reduced velocity.High response amplitudes are found when the response frequency is between the first and the highest modal frequencies.In a multiple-cylinder system,the single-mode response,where the vibration is dominated by one mode,can be only found in low reduced velocity range.In the single-mode branch,the dominance of a single mode shape in the response can be clearly identified except at the boundary reduced velocity between two modes.The maximum response amplitude occurs in the multiple-mode response and interaction between the vortices in the wake of the cylinders is strong when the response amplitudes are high.