Experimental Investigation of Vortex-Induced Vibration in One and Two Dimensions With Variable Mass, Damping, and Reynolds Number

Abstract

Measurements are made of vortex-induced vibration of an elastically supported circular cylinder in water with reduced velocity (U/fnD) from 2 to 12, damping factors (ζ) from 0.2% to 40% of critical damping, mass ratios (m/ρD2) from π/2 to π/17, and transverse, inline, and combined inline and transverse motions at Reynolds numbers up to 150,000. Effects of mass, damping, Reynolds number, and strakes on vortex-induced vibration amplitude, frequency, entrainment, and drag are reported.

Vortex-induced vibrations of a freely vibrating cylinder near a plane boundary: Experimental investigation and theoretical modelling

“…In their report, Blevins et al also present the results for different damping values and different mass ratios, and conclude that by decreasing the damping the amplitude of oscillations increases and that by decreasing the mass ratio the lock-in region widens. These conclusions are consistent with the differences verified between this report and reference [10].  as functions of the reduced velocity r V for the four gap ratios considered in this group.…”

“… as functions of the reduced velocity r V for the four gap ratios considered in this group. The mean in-line coefficients are accompanied by the results reported in reference [10]. Both the mean (Figure 7a) and the oscillating (Figures 7b,d) coefficients assume the maximum value at the reduced velocity 5 r V  , which also corresponds to the onset of the lock-in region.…”

“…If the cylinder is free to move, amplifications of its response may occur when the shedding frequency approaches and subsequently locks onto the cylinder's natural frequency. This amplification of the vortex-induced vibrations (VIV) has been investigated since the second half of the 20 th century, and reports on several experimental works can be found in literature [1][2][3][4][5][6][7][8][9][10]. Based on the presented results, some simple models for the prediction of the flow-induced response of cylinders have been constructed.…”

“…These types of experiments can be divided into three distinct groups: (i) stationary experiments, in which the cylinder is fixed and the acting forces are measured [1]; (ii) forced vibration experiments, in which an immersed cylinder is forced to move with a given amplitude and frequency, and the fluid forces are registered [2,3]; and (iii) free vibration experiments, in which a cylinder can vibrate freely in the flow, and its motion is recorded [3][4][5][6][7][8][9][10].…”

Vortex-Induced Vibration Tests of a Marine Growth Wrapped Cylinder at Subcritical Reynolds Number

“…The Reynolds number is defined as Re = UD/ѵ where ѵ = 10 -6 m 2 /s is the kinematic viscosity of water at room temperature and the Strouhal number is defined as St=f s D/U, where U is the fluid velocity, D is the diameter of the cylinder and f s is the shedding frequency. The fluid-structure coupling is characterized by the reduced velocity U r =U/ f s D. For instance Feng [1][2][3][4][5][6] investigated the VIV of circular cylinders. The pioneering experimental investigation conducted to assess the effects of surface roughness on the pressure distribution around a bluf body was conducted by Fage and Warsap [7].…”