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The formation of vortex streets

Published online by Cambridge University Press:  28 March 2006

Frederick H. Abernathy
Affiliation:
Division of Engineering and Applied Physics, Harvard University, Cambridge, Massachusetts
Richard E. Kronauer
Affiliation:
Division of Engineering and Applied Physics, Harvard University, Cambridge, Massachusetts

Abstract

The formation of vortex streets in the wake of two-dimensional bluff bodies can be explained by considering the non-linear interaction of two infinite vortex sheets, initially a fixed distance, h, apart, in an inviscid incompressible fluid. The interaction of such sheets (represented in the calculation by rows of point-vortices) is examined in detail for various ratios of h to the wavelength, a, of the initial disturbance. The number and strength of the concentrated regions of vorticity formed in the interaction depend very strongly on h/a. The non-linear interaction of the two vortex sheets explains both the cancellation of vorticity and vortex-street broadening observed in the wakes of bluff bodies.

Type
Research Article
Copyright
© 1962 Cambridge University Press

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