Structural Engineering and Mechanics

Volume 75, Number 5, 2020, pages 621-631

DOI: 10.12989/sem.2020.75.5.621

Vortex-induced vibration characteristics of a low-mass-ratio flexible cylinder

Lee Kee Quen, Aminudin Abu, Naomi Kato, Pauziah Muhamad, Kang Hooi Siang, Lim Meng Hee and Mohd Asamudin A Rahman

Abstract

A laboratory experiment is conducted is to investigate the behaviour of a low-mass-ratio and high aspect ratio flexible cylinder under vortex-induced vibration (VIV). A flexible cylinder with aspect ratio of 100 and mass ratio of 1.17 is towed horizontally to generate uniform flow profile. The range of Reynolds number is from 1380 to 13800. Vibration amplitude, in-line and cross-flow frequency response, amplitude trajectory, mean tension variation and hydrodynamic force coefficients are analyzed based on the measurement from strain gauges, load cell and CCD camera. Experimental results indicate that broad-banded lock-in region is found for the cylinder with a small Strouhal number. The frequency switches in the present study indicates the change of the VIV phenomenon. The hydrodynamic force responses provide more understanding on the VIV of a low mass ratio cylinder.

Key Words

vortex-induced vibration; low mass ratio; high aspect ratio; flexible cylinder

Address

Lee Kee Quen, Aminudin Abu, Pauziah Muhamad: Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Kuala Lumpur, 54100 Malaysia Naomi Kato: Department of Naval Architecture and Ocean Engineering, Graduate School of Engineering, Osaka University, Japan Kang Hooi Siang: 1) School of Mechanical Engineering, Universiti Teknologi Malaysia, Malaysia 2) Marine Technology Center, Institute for Vehicle System and Engineering, Universiti Teknologi Malaysia, Malaysia Lim Meng Hee: Institute of Noise and Vibration, Universiti Teknologi Malaysia, Kuala Lumpur, Malaysia Mohd Asamudin A Rahman: School of Ocean Engineering, Universiti Malaysia Terengganu, Terengganu 21030, Malaysia