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On the shock cell structure and noise of supersonic jetsA linear solution modeling the shock cell structure of an axisymmetric supersonic jet operated at off-design conditions is developed by the method of multiple-scales. The model solution takes into account the gradual spatial change of the mean flow in the downstream direction. Turbulence in the mixing layer of the jet has the tendency of smoothing out the sharp velocity and density gradients induced by the shocks. To simulate this effect, eddy viscosity terms are incorporated in the model. It is known that the interaction between the quasi-periodic shock cells and the downstream propagating large turbulence structures in the mixing layer of the jet is responsible for the generation of broadband shock associated noise. Experimentally, the dominant part of this noise has been found to originate from the part of the jet near the end of the potential core. Calculated shock cell spacing at the end of the jet core according to the present model is used to estimate the peak frequencies of the shock associated noise for a range of observation angles. Very favorable agreement with experimental measurements is found.
Document ID
19830044705
Document Type
Conference Paper
Authors
Tam, C. K. W.
(Florida State University Tallahassee, FL, United States)
Jackson, J. A.
(Florida State Univ. Tallahassee, FL, United States)
Date Acquired
August 11, 2013
Publication Date
April 1, 1983
Subject Category
Acoustics
Report/Patent Number
AIAA PAPER 83-0703
Meeting Information
American Institute of Aeronautics and Astronautics, Aeroacoustics Conference(Atlanta, GA)
Funding Number(s)
CONTRACT_GRANT: NAG3-182
Distribution Limits
Public
Copyright
Other
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