Effects of forward velocity on noise for a J85 turbojet engine with multitube suppressor from wind tunnel and flight testsFlight tests and wind tunnel noise tests using a J85 engine with some representative jet exhaust noise suppressors are reported. Capabilities and limitations of the two types of experimental methods are evaluated with emphasis on investigation of forward velocity effects. The suppressor arrangement was a 104-elliptical-tube nozzle configuration, with or without an acoustically lined shroud. The suppressor noise levels are found not reduced as much by forward velocity as expected for unsuppressed jets. The directivity and forward velocity effects appear more similar to predicted trends for internally generated noise than for unsuppressed jet noise.
Document ID
19770061608
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Stone, J. R. (NASA Lewis Research Center Cleveland, OH, United States)
Miles, J. H. (NASA Lewis Research Center Cleveland, OH, United States)
Sargent, N. B. (NASA Lewis Research Center Cleveland, Ohio, United States)
Date Acquired
August 9, 2013
Publication Date
November 1, 1976
Subject Category
Aircraft Propulsion And Power
Meeting Information
Meeting: Meeting of the Acoustical Society of America