Hostname: page-component-77c89778f8-rkxrd Total loading time: 0 Render date: 2024-07-18T06:22:47.131Z Has data issue: false hasContentIssue false

The stability of three-dimensional time-periodic flows with spatially uniform strain rates

Published online by Cambridge University Press:  26 April 2006

A. D. D. Craik
Affiliation:
Department of Mathematical & Computational Sciences, University of St. Andrews, St. Andrews, Fife, KY16 9SS, Scotland
H. R. Allen
Affiliation:
Department of Mathematical & Computational Sciences, University of St. Andrews, St. Andrews, Fife, KY16 9SS, Scotland

Abstract

Unbounded incompressible fluid in solid-body rotation is subjected to spatially uniform strain rates that are sinusoidal in time and of arbitrarily large amplitude. The exact governing equations for the evolution of plane-wave disturbances to this time-periodic flow are linear, as for related steady flows. Attention focuses mainly on the in viscid problem, since incorporation of viscosity is straightforward.

Plane-wave disturbances to axisymmetric flows are governed by a Hill's equation, or equivalently, a pair of first-order equations, to which Floquet theory is applied. Analytical and computational results show several instability bands, the first few of which can exhibit large growth rates. The exact governing equations for plane-wave disturbances to non-axisymmetric flows are similarly derived; but, as these are not singly periodic, results are given only for small-amplitude periodic forcing. As the non-axisymmetric strain produces a periodic elliptical distortion of the flow, a modified elliptical-instability mechanism joins that present in axisymmetric cases.

Despite necessary idealizations, the analysis and results shed light on the stability of periodically strained vortices in a turbulent environment and in geophysical contexts.

Type
Research Article
Copyright
© 1992 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

Abramowitz, M. & Stegun, I. A. (eds.) 1965 Handbook of Mathematical Functions. Dover.
Barr, A. D. S. & McWhannell, D. C. 1971 J. Sound Vib. 14, 491509.
Bayly, B. J. 1986 Phys. Rev. Lett. 57, 21602171.
Bayly, B. J., Orszag, S. A. & Herbert, T. 1989 Ann. Rev. Fluid Mech. 20, 359391.
Benjamin, T. B. & Ursell, F. 1954 Proc. R. Soc. Lond. A 225, 505515.
Craik, A. D. D. 1985 Wave Interactions and Fluid Flows. Cambridge University Press.
Craik, A. D. D. 1988 Proc. R. Soc. Lond. A 417, 235244.
Craik, A. D. D. 1989 J. Fluid Mech. 198, 275292 (referred to herein as II).
Craik, A. D. D. 1991 In Nonlinear Dynamics of Structures: Proc. Internat. Symp. Perm-Moscow (ed. R. Z. Sagdeev, U. Frisch, S. S. Moiseev & N. Erokhin), pp. 293293. World Scientific.
Craik, A. D. D. & Criminale, W. O. 1986 Proc. R. Soc. Lond. A 406, 1326 (referred to herein as I).
Dritschel, D. G. 1986 J. Fluid Mech. 172, 157182.
Dritschel, D. G. 1990 J. Fluid Mech. 210, 223261.
Faraday, M. 1831 Phil. Trans. R. Soc. Lond. 121, 299340.
Gledzer, E. B., Dolzhansky, F. V., Obukhov, A. M. & Ponomarev, V. M. 1975 Izv. Atmos. Ocean. Phys. 11, 617622.
Gledzer, E. B. & Ponomarev, V. M. 1992 Elliptical instability theory of bounded flows. J. Fluid Mech. (submitted).Google Scholar
Haynes, P. H. 1987 J. Fluid Mech. 175, 463478.
Johnson, R. & Moser, J. 1982 Commun. Math. Phys. 84, 403438.
Kelvin, Lord 1887 Phil. Mag. 24 (5), 188196.
Kevorkian, J. & Cole, J. D. 1981 Perturbation Methods in Applied Mathematics. Springer.
Klotter, K. & Kotowski, G. 1943 Z. Angew. Math. Mech. 23, 149155.
Lagnado, R. R., Phan-Thien, N. & Leal, L. G. 1984 Phys. Fluids 27, 10941101.
Landman, M. J. & Saffman, P. G. 1987 Phys. Fluids 30, 23392342.
McEwan, A. D. & Robinson, R. M. 1975 J. Fluid Mech. 67, 667687.
Magnus, W. & Winkler, S. 1966 Hill's Equation. Wiley.
Malkus, W. V. R. 1989 Geophys. Astrophys. Fluid Dyn. 48, 123143.
Mansour, N. N. & Lundgren, T. S. 1990 Phys. Fluids A 2, 20892091.
Miles, J. W. & Henderson, D. 1990 Ann. Rev. Fluid Mech. 22, 143165.
Nayfeh, A. H. & Mook, D. T. 1979 Nonlinear Oscillations. Wiley.
Othman, A. M., Watt, D. & Barr, A. D. S. 1987 J. Sound Vib. 112, 249259.
Pearson, J. R. A. 1959 J. Fluid Mech. 5, 274288.
Pierrehumbert, R. T. 1986 Phys. Rev. Lett. 57, 21572159.
Robinson, A. C. & Saffman, P. G. 1984 J. Fluid Mech. 142, 451466.
Vladimirov, V. A. 1983 Prikl. Mech. Tekh. Fiz. (no. 4), 3961.
Waleffe, F. 1990 Phys. Fluids A 2, 7680.