Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/24547
Title: Vortex-induced vibration characteristics of an elastic square cylinder on fixed supports
Authors: Wang, ZJ
Zhou, Y
Keywords: Damping ratio
Elastic cylinder
Flow separation
Vortex-induced vibration
Issue Date: 2005
Publisher: ASME-Amer Soc Mechanical Eng
Source: Journal of fluids engineering, transactions of the asme, 2005, v. 127, no. 2, p. 241-249 How to cite?
Journal: Journal of Fluids Engineering, Transactions of the ASME 
Abstract: The vortex-induced structural vibration of an elastic square cylinder, on fixed supports at both ends, in a uniform cross flow was measured using fiber-optic Bragg grating sensors. The measurements are compared to those obtained for an elastic circular cylinder of the same hydraulic diameter in an effort to understand the effect of the nature (fixed or oscillating) of the flow separation point on the vortex-induced vibration. It is found that a violent vibration occurs at the third-mode resonance when the vortex-shedding frequency coincides with the third-mode natural frequency of the fluid-structure system, irrespective of the cross-sectional geometry of the cylinder. This is in distinct contrast to previous reports of flexibly supported rigid cylinders, where the first-mode vibration dominates, thus giving little information on the vibration of other modes. The resonance behavior is neither affected by the incidence angle (a) of the free stream, nor by the nature of the flow separation point. However, the vibration amplitude of the square cylinder is about twice that of the circular cylinder even though the flexural rigidity of the former is larger. This is ascribed to a difference in the nature of the flow separation point between the two types of structures. The characteristics of the effective modal damping ratios, defined as the sum of structural and fluid damping ratios, and the system natural frequencies are also investigated. The damping ratios and the system natural frequencies vary little with the reduced velocity at α=0 deg, but appreciable at α ≥15 deg; they further experience a sharp variation, dictated by the vortex-sheddine freauency, near resonance.
URI: http://hdl.handle.net/10397/24547
ISSN: 0098-2202
DOI: 10.1115/1.1881693
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

12
Last Week
1
Last month
0
Citations as of Oct 8, 2017

WEB OF SCIENCETM
Citations

10
Last Week
0
Last month
0
Citations as of Oct 15, 2017

Page view(s)

30
Last Week
0
Last month
Checked on Oct 15, 2017

Google ScholarTM

Check

Altmetric



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.