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Effects of external boundary layer flow on jet noise in flightThe effects on jet flow of the external boundary layer flow emanating from the trailing edge of an engine cowl in flight has been shown to be the main reason for the disparity between predicted and experimental results obtained from flight measurements. Flight simulation experiments indicate that the external boundary layer flow tends to shield the jet flow in flight. This in turn modifies the jet noise source in flight and consequently the radiated noise from aircraft in flight. Close to 90 deg angle to the intake and in the forward quadrant, this study indicates that the far field jet noise and its spectrum scales approximately with the absolute jet velocity instead of the relative velocity as has been assumed in the existing prediction models.
Document ID
19760055109
Document Type
Conference Paper
Authors
Sarohia, V. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Massier, P. F. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena Calif., United States)
Date Acquired
August 8, 2013
Publication Date
July 1, 1976
Subject Category
ACOUSTICS
Report/Patent Number
AIAA PAPER 76-558
Meeting Information
Aero-Acoustics Conference(Palo Alto, CA)
Funding Number(s)
CONTRACT_GRANT: NAS7-100
Distribution Limits
Public
Copyright
Other