DIFFERENT MODES OF VORTEX SHEDDING: AN OVERVIEW
Author: Zdravkovich M.M.
Source: Journal of Fluids and Structures, Volume 10, Number 5, July 1996 , pp. 427-437(11)
Publisher: Academic Press
Abstract:
An enormous research effort has been expended on the flow around bluff bodies for over a century. This paper is an attempt to categorize the observed modes of vortex shedding. First, the low-speed mode caused by the laminar wake instability is juxtaposed to the high-speed mode controlled by the mechanics of vortex formation and shedding. Particular attention is given to the transition from the low-speed to high-speed mode. Second, the discussion is directed to the synchronized vortex shedding, when the transverselly oscillating cylinder takes over the control of frequency of vortex shedding. Again, two modes exist, although the frequency remains unchanged. The phase angle between the force exerted on the cylinder by the fluid and its displacement shows a discontinuous jump in the middle of the synchronization range where a maximum amplitude is reached for the free-oscillating cylinder. This is caused by the sudden 180#&176; change in phase of vortex shedding. Third, yet another synchronized vortex shedding is described that is caused by the streamwise oscillation of a cylinder or when a stationary cylinder is submerged in oscillatory flows. Again, two shedding modes are found by Griffin and co-workers, with a distinct single vortex or two vortices shed during each half-cycle, respectively.
Language: English
Document Type: Research article
Affiliations: Telford Institute, University of Salford, Salford, M5 4WT, U.K.:

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