The Vibration Response of a Cantilevered Rectangular Cylinder in Cross-Flow Oscillation

Abstract

It is well known that a large-amplitude oscillation called galloping 123 is generated, in addition to Kármán vortex excitation, for rectangular cylinders supported perpendicularly to a uniform flow when the slenderness b/d is in the range of 0.6 to 2.8 (d=height, b=streamwise length of the rectangular cross-section). The basic aerodynamic excitation mechanism of the cross-flow galloping of a rectangular cylinder is explained by the quasi-steady nonlinear aerodynamic theory developed by Parkinson et al. 4. In this theory, the relative attack angle plays an important role in the excitation mechanism of galloping. Also, as was shown by Deniz and Staubli 5, the attack angle of a fixed rectangular cylinder strongly affects the vortex shedding frequency and lift.