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The development of Long's vortex

Published online by Cambridge University Press:  26 April 2006

P.G. Drazin
Affiliation:
School of Mathematics, University of Bristol, Bristol BS8 1TW, UK
W.H.H. Banks
Affiliation:
School of Mathematics, University of Bristol, Bristol BS8 1TW, UK
M.B. Zaturska
Affiliation:
School of Mathematics, University of Bristol, Bristol BS8 1TW, UK

Abstract

This paper describes the solution of Long's problem for steady rotationally symmetric swirling jets in a uniform viscous fluid. Long found these vortices in 1958 by assuming a similarity form of solution, and in 1961 solved the consequent problem in the boundary-layer limit, finding dual solutions. The overall pattern of the solutions to the problem for general values of the Reynolds number is described. The linear spatial stability of the flows to small steady disturbances is analysed and a few results presented. In particular, details of the solutions and their stability are given asymptotically for small and large values of the Reynolds number. The asymptotic results for the basic flow are linked by direct numerical integration of the flow at several finite positive values of the Reynolds number.

Type
Research Article
Copyright
© 1995 Cambridge University Press

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References

Abramowitz, M. & Stegun, I. A. 1964 Handbook of Mathematical Functions. Washington, DC: National Bureau of Standards.
Banks, W.H.H., Drazin, P.G. & Zaturska, M. B. 1988 On perturbations of Jeffery—Hamel flow. J. Fluid Mech. 186, 559581.Google Scholar
Batchelor, G. K. & Gill, A. E. 1962 Analysis of the stability of axisymmetric jets. J. Fluid Mech. 14, 529551.Google Scholar
Burggraf, O. R. & Foster, M. R. 1977 Continuation or breakdown in tornado-like vortices. J. Fluid Mech. 80, 685703.Google Scholar
Foster, M. R. & Duck, P. W. 1982 The inviscid instability of Long's vortex. Phys. Fluids 25, 17151718.Google Scholar
Foster, M. R. & Jacqmin, D. 1992 Non-parallel effects in the instability of Long's vortex. J. Fluid Mech. 244, 289306.Google Scholar
Foster, M. R. & Smith, F. T. 1989 Stability of Long's vortex at large flow force. J. Fluid Mech. 206, 405432.Google Scholar
Hall, M. G. 1966 The structure of concentrated vortex cores. Prog. Aero. Sci. 7, 53110.Google Scholar
Hall, M. G. 1972 Vortex breakdown. Ann. Rev. Fluid Mech. 4, 195217.Google Scholar
Khorrami, M. R. & Trivedi, P. 1994 The viscous stability analysis of Long's vortex. Phys. Fluids 6, 26232630.Google Scholar
Leibovich, S. 1978 The structure of vortex breakdown. Ann. Rev. Fluid Mech. 10, 221246.Google Scholar
Long, R. R. 1958 Vortex motion in a viscous fluid. J. Met. 15, 108112.Google Scholar
Long, R. R. 1961 A vortex in an infinite viscous fluid. J. Fluid Mech. 11, 611624.Google Scholar
Shtern, V. & Hussain, F. 1993 Hysteresis in a swirling jet as a model tornado. Phys. Fluids A 5, 21832195.Google Scholar
Stewartson, K. 1982 The stability of swirling flow at large Reynolds number when subjected to disturbances with large azimuthal wavenumber. Phys. Fluids 25, 19531958.Google Scholar