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Controlled interactions in a forced axisymmetric jet. Part 1. The distortion of the mean flow

Published online by Cambridge University Press:  26 April 2006

T. A. Long
Affiliation:
Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721, USA
R. A. Petersen
Affiliation:
Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721, USA Current address: Jet Propulsion Laboratory, Pasadena, CA 91109, USA.

Abstract

Controlled resonant interactions between two spinning waves in a turbulent, axisymmetric air jet are documented. Interactions betwen two helical waves with spinning mode numbers of +m and −m induced a cos(2mϕ) distortion of the mean cross-section. The shape and orientation of the distortion were predictable based on the standing wave pattern. Square and elliptical jets were produced in this way and the spatial distribution of the coherent large-scale motion is documented. The elliptical distortion was comparable in magnitude to a jet issuing from a 2:1 elliptical nozzle. A near-resonance case produced from spinning mode numbers of m = 0 and + 2 was also examined.

Type
Research Article
Copyright
© 1992 Cambridge University Press

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References

Cohen, J. & Wygnanski, I. 1987 The evolution of instabilities in the axisymmetric jet. J. Fluid Mech. 176, 191235.Google Scholar
Crow, S. C. & Champagne, F. H. 1971 Orderly structure in jet turbulence. J. Fluid Mech. 48, 547591.Google Scholar
Gaster, M., Kit, E. & Wygnanski, I. J. 1985 Large-scale structures in a forced turbulent mixing layer. J. Fluid Mech. 150, 2339.Google Scholar
Ho, C. M. & Gutmark, E. 1987 Vortex induction and mass entrainment in a small-aspect-ratio elliptic jet. J. Fluid Mech. 179, 383405.Google Scholar
Husain, H. S. & Hussain, A. K. M. F. 1983 Controlled excitation of elliptic jets. Phys. Fluids 26, 27632766.Google Scholar
Hussain, A. K. M. F. & Reynolds, W. C. 1970 The mechanics of an organized wave in turbulent shear flow. J. Fluid Mech. 41, 241258.Google Scholar
Long, T. A. 1988 The controlled interaction of excited modes in an axisymmetric jet. M.S. dissertation, University of Arizona, Tucson.
Petersen, R. A. 1978 Influence of wave dispersion on vortex pairing in a jet. J. Fluid Mech. 89, 469495.Google Scholar
Petersen, R. A. & Long, T. A. 1992 Controlled interactions in a forced axisymmetric jet. Part 2. The modulation of broadband turbulence. J. Fluid Mech. 235, 5771.Google Scholar
Petersen, R. A. & Samet, M. M. 1988 On the preferred mode of jet instability. J. Fluid Mech. 194, 153173.Google Scholar
Petersen, R. A., Samet, M. M. & Long, T. A. 1987 Excitation of azimuthal modes in an axisymmetric jet. In IUTAM Symp. on Turbulence Management and Relaminarization, Bangalore, India.
Phillips, O. M. 1974 Wave interactions. In Nonlinear Waves (ed. S. Leibovich & A. R. Seebass), pp. 186211. Cornell University Press.
Samet, M. M. & Petersen, R. A. 1988 Effects of excitation level on the stability of an axisymmetric mixing layer. Phys. Fluids 31, 32463252.Google Scholar
Strange, P. J. R. 1981 Spinning modes in orderly jet structure and jet noise. Ph.D. dissertation, University of Leeds.
Strange, P. J. R. & Crighton, D. G. 1985 Spinning modes on axisymmetric jets. Part 1. J. Fluid Mech. 134, 231245.Google Scholar
Wygnanski, I. J., Champagne, F. H. & Marasli, B. 1986 On the large-scale structures in two-dimensional, small-deficit, turbulent wakes. J. Fluid Mech. 168, 3171.Google Scholar
Wygnanski, I. & Petersen, R. A. 1987 Coherent motion in excited free shear flows. AIAA J. 25, 201213.Google Scholar