NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Supersonic jet noise reduction by coaxial rectangular nozzlesA physical understanding of noise reduction mechanisms in supersonic, single, and coaxial rectangular jets is quantified and obtained, with emphasis on shock noise reduction. For all conditions, corresponding acoustic measurements for an equivalent round jet are also obtained so that the noise characteristics of the two types of jets can be compared directly to quantify the noise reductions. Comparisons are thus provided for a single rectangular nozzle vs a single equivalent round nozzle, and a coaxial rectangular nozzle vs an equivalent round nozzle. It is shown that different operating conditions and nozzle arrangements for the same thrust, total exit area, and mass flow rate can produce different noise levels. With at least one stream operated supersonically, the coaxial rectangular nozzle operated in the inverted-velocity profile is always quieter than in the normal velocity profile mode for the same thrust, exit area, and mass flow rate. In general, the coaxial rectangular nozzle is shown to be quieter than an equivalent circular nozzle only for those conditions for which both nozzles are operated supersonically.
Document ID
19930035208
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Ahuja, K. K.
(NASA Lewis Research Center Cleveland, OH, United States)
Manes, J. P.
(NASA Lewis Research Center Cleveland, OH, United States)
Massey, K. C.
(Georgia Inst. of Technology Atlanta, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1992
Publication Information
Publication: In: DGLR(AIAA Aeroacoustics Conference, 14th, Aachen, Germany, May 11-14, 1992, Proceedings. Vol. 2 (A93-19126 05-71)
Publisher: Deutsche Gesellschaft fuer Luft- und Raumfahrt
Subject Category
Acoustics
Accession Number
93A19205
Funding Number(s)
CONTRACT_GRANT: NAG3-1066
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available