Surface and Wake Flow Phenomena of the Vortex-Excited Oscillation of a Circular Cylinder

Using an original design of acoustic-level pressure transducer, measurements were made of fluctuating pressures on the surface and in the wake of a circular cylinder at rest and in vortex-excited oscillation at subcritical Reynolds numbers. Frequency, amplitude, and phase, where relevant, of the cylinder oscillation were also measured, and some effects of cylinder oscillation on the organized wake geometry were observed. The new results are compared with relevant existing information for the stationary cylinder, and with the few measurements previously available for the oscillating cylinder, and some analysis is made.