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Turbulent mixing noise from supersonic jetsThere is now a substantial body of theoretical and experimental evidence that the dominant part of the turbulent noise of supersonic jets is generated directly by the large turbulence structures/instability waves of the jet flow. Earlier, Tam and Burton provided a description of the physical mechanism by which supersonically traveling instability waves can generate sound efficiently. They used the method of matched asymptotic expansions to construct an instability wave solution which is valid in the far field. The present work is an extension of the theory of Tam and Burton. It is argued that the instability wave spectrum of the jet may be regarded as generated by stochastic white noise excitation at the nozzle lip region. The reason why the excitation has white noise characteristics is that near the nozzle lip region the flow in the jet mixing layer has no intrinsic length and time scales. The present stochastic wave model theory of supersonic jet noise contains a single unknown multiplicative constant. Comparisons between the calculated noise directivities at selected Strouhal numbers and experimental measurements of a Mach 2 jet at different jet temperatures have been carried out. Favorable agreements are found.
Document ID
19950061715
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Tam, Christopher K. W.
(Florida State Univ. Tallahasse, FL, United States)
Chen, Ping
(Florida State Univ. Tallahasse, FL, United States)
Date Acquired
August 16, 2013
Publication Date
September 1, 1994
Publication Information
Publication: AIAA Journal
Volume: 32
Issue: 9
ISSN: 0001-1452
Subject Category
Fluid Mechanics And Heat Transfer
Accession Number
95A93314
Funding Number(s)
CONTRACT_GRANT: NAG1-421
Distribution Limits
Public
Copyright
Other

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