Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-13T01:29:10.707Z Has data issue: false hasContentIssue false

The instability of inviscid jets and wakes in compressible fluid

Published online by Cambridge University Press:  28 March 2006

M. Lessen
Affiliation:
Department of Mechanical and Aerospace Sciences, The University of Rochester, Rochester, N.Y.
J. A. Fox And
Affiliation:
Department of Mechanical and Aerospace Sciences, The University of Rochester, Rochester, N.Y.
H. M. Zien
Affiliation:
Department of Mechanical and Aerospace Sciences, The University of Rochester, Rochester, N.Y.

Abstract

The instability of a two-dimensional jet with respect to three-dimensional disturbances and that of an axially symmetric jet with respect to azimuthally periodic disturbances are studied, for the inviscid flow of a compressible fluid. In both cases the undisturbed velocity is assumed to be uniform in the jet. It is shown analytically that a two-dimensional jet is unstable under small disturbances, either subsonic or supersonic. There is no upper limit in Mach number, as was found for a plane vortex sheet, above which the flow is completely stable. Numerical calculations for the eigenvalues for both the two-dimensional jet and the axially symmetric jet have been made. The results indicate that the increase of Mach number tends to stabilize the flow. For the two-dimensional jet, the larger the angle between the direction of wave propagation and that of the main flow, the more the flow will be destabilized. For the axially symmetric jet, the flow is more unstable under azimuthally periodic disturbances than under rotationally symmetric ones, at small wave number.

Type
Research Article
Copyright
© 1965 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

Batchelor, G. K. & Gill, A. E. 1962 J. Fluid Mech. 14, 529.
Fejer, J. A. & Miles, John W. 1963. J. Fluid Mech. 15, 335.
Hatanaka, Hiroshi 1949 J. Soc. Sci. Culture, 2, 3; cited by Appl. Mech. Rev. 2, 897.
Landau, L. 1944 C. R. Acad. Sci., U.S.S.R., 44, 139.
Lin, C. C. 1953 Nat. Adv. Comm. Aero., Wash., Tech. Note, no. 2887.
Lin, C. C. 1955 The Theory of Hydrodynamic Stability. Cambridge University Press.
Miles, J. W. 1958 J. Fluid Mech. 4, 538.
Pai, S. I. 1954 J. Aero. Sci. 21, 325.