Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-13T01:35:09.226Z Has data issue: false hasContentIssue false

A numerical study of the roll-up of a finite vortex sheet

Published online by Cambridge University Press:  29 March 2006

D. W. Moore
Affiliation:
Department of Mathematics, Imperial College, London

Abstract

A point-vortex representation is used to study numerically the evolution of an initially plane vortex sheet. By introducing a tip vortex to represent the tightly rolled portion of the vortex sheet, the chaotic motion which was a feature of some earlier studies is eliminated and the details of the outer portion of the spiral are calculated. The rate of rolling up is calculated and is shown to be governed by the analytically predicted similarity law of Kaden during the initial stages of the rolling up. The calculations are continued until 99% of the vorticity has been rolled up, at which stage the spiral displays a marked ellipticity.

Type
Research Article
Copyright
© 1974 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Chorin, A. J. & Bernard, P. S. 1972 Discretization of a vortex sheet, with an example of roll-up. (To appear.)
Clements, R. R. & Maull, D. J. 1973 The rolling up of a trailing vortex sheet. Aero. J. 77, 46.Google Scholar
Crow, S. 1965 Ph.D. Thesis, California Institute of Technology.
Kaden, H. 1931 Aufwicklung einer unstabilen Unstetigkeitsflilche. Ing. Archiv. 2, 140. (English trans. R.A.E. Library Trans. no. 403.)Google Scholar
Kuwahara, K. & Takami, H. 1973 Numerical studies of two-dimensional vortex motion by a system of point vortices. J. Phys. Soc. Japan, 34, 247.Google Scholar
Lamb, H. 1932 Hydrodynamics. Cambridge University Press.
Moore, D. W. 1971 The discrete vortex approximation of a vortex sheet. California Inst. of Tech. Rep. Afosr-1084-69.
Nielsen, J. N. & Schwind, R. G. 1971 Decay of a vortex pair behind an aircraft. Aircraft Wake Turbulence and its Detection, p. 413. Plenum.
Smith, J. H. B. 1968 Improved calculations of leading-edge separation from slender delta wings. Proc. Roy. Soc. A 306, 67.Google Scholar
Takami, H. 1964 A numerical experiment with discrete vortex approximation with reference to the rolling up of a vortex sheet. Dept. of Aeron. & Astron., Stanford University, SUDAER 202.
Westwater, F. L. 1935 Rolling up of the surface of discontinuity behind an aerofoil of finite span. Aero. Res. Counc. R. & M. no. 1962.