An evaluation of various concepts of reducing supersonic jet noiseAcoustic and flow visualization data from nozzles mounted on the same facility were acquired, and a total of 10 different concepts of jet noise suppression were evaluated relative to one another and also a round nozzle. All nozzles had the same exit area. The suppressors included noncircular shapes; nozzles fitted with notches, tabs, and ejectors; and coaxial rectangular nozzles. Narrow-band noise data were acquired by a microphone located in the plane of the jet exit. In general, it is found that, for a constant exit area, the round nozzle is the noisiest. Just about any modification of this round nozzle around its periphery reduces the broadband shock-associated noise and, in most instances, modifies the screech frequency and levels. Coaxial rectangular nozzles, nozzles fitted with two tabs and operated with ejectors, and a rectangular C-D nozzles with perforated walls are identified to be the most promising concepts worthy of further investigation.
Document ID
19910027872
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Ahuja, K. K. (Georgia Institute of Technology Atlanta, United States)
Manes, J. P. (Georgia Inst. of Tech. Atlanta, GA, United States)
Massey, K. C. (Georgia Inst. of Tech. Atlanta, GA, United States)
Calloway, A. B. (Georgia Inst. of Tech. Atlanta, GA, United States)