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Tones Encountered with a Coannular Nozzle and a Method for their SuppressionWith multi-stream coannular nozzles, sometimes tones occur that may cause the nozzle to fail noise regulation standards. A two-stream nozzle was studied experimentally and numerically in an at-tempt to identify the sources of such tones and explore remedies. For the given nozzle configuration, sharp tones occurred in a range of low jet Mach numbers. The tones apparently occurred due to a coupling between vortex shedding from the struts, which held the nozzles and the center-body together, with various duct acoustic modes. A leading edge treatment of the struts is shown to eliminate the tones via disruption of the vortex shedding.
Document ID
Acquisition Source
Glenn Research Center
Document Type
Conference Paper
Zaman, K. B. M. Q.
(NASA Glenn Research Center Cleveland, OH United States)
Bridges, J. E.
(NASA Glenn Research Center Cleveland, OH United States)
Fagan, A. F.
(NASA Glenn Research Center Cleveland, OH United States)
Miller, C. J.
(NASA Glenn Research Center Cleveland, OH United States)
Date Acquired
June 27, 2017
Publication Date
June 5, 2017
Subject Category
Numerical Analysis
Aircraft Propulsion And Power
Report/Patent Number
Meeting Information
Meeting: American Institute of Aeronautics and Astronautics (AIAA) Aviation Forum 2017
Location: Denver, CO
Country: United States
Start Date: June 5, 2017
End Date: June 9, 2017
Sponsors: American Inst. of Aeronautics and Astronautics
Funding Number(s)
WBS: WBS 110076.
Distribution Limits
Work of the US Gov. Public Use Permitted.
vortex shedding
duct resonance
acoustic tones
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