On the vortex-induced vibration of a low mass ratio circular cylinder near a planar boundary

Abstract

Vortex-induced vibration of a circular cylinder near a plane boundary has been investigated experimentally for 2,500≤ReD≤10,000, 3.0≤U*≤12.0, 0.3≤S*≤8, and m*=5.3, where ReD is the Reynolds number based on cylinder diameter, U* is the reduced velocity, S* is the gap distance between the planar wall and the cylinder, and m* is the system's mass ratio. The experimental data includes simultaneous amplitude response and wake measurements via time-resolved planar particle image velocimetry (PIV). From experimental raw data, frequency content of the oscillations as well as wake velocity and vorticity fields are analyzed. A new vortex shedding flow regime map is proposed, illustrating dominant vortex shedding patterns in the wake across the investigated non-dimensional parameter space. The quantitative relationship between the cylinder's motion and instantaneous vortex dynamics is shown.