GALCIT Home Page
| 2000-2001 Fluids Seminar Page |
Mechanical, Aerospace and Manufacturing Engineering
Syracuse University
Abstract-
Fluid-structure interactions and their control in many practical
applications rely on the understanding of the wake behind bluff bodies. The
experimental study presented is motivated by so-called wake-recontact
problems with high-performance parachutes; it examines the evolution of the
wake structure behind a disk and other bluff-bodies. Behind the impulsively
started disk, the growth of the wake size and circulation time history
scaled with the velocity and the disk diameter over a wide range of the
Reynolds numbers tested. The maximum normalized circulation reached an
asymptotic value after which the vortex started to deform and eventually
shed downstream asymmetrically. This maximum circulation is analogous to the
formation number for the vortex ring (Gharib et al, 1998.) The results will
be compared with those behind the uniformly accelerated disk and a flat
plate. [The wake study is currently being extended to supersonic speeds as
well as to the wake behind a magnetically suspended model.] The talk will
conclude with related wake structure interaction problems in sports
aerodynamics pertaining to the knuckleball and flying disk.
|
GALCIT Home Page
|
|