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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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