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Hybrid Wing Body (HWB) Slat Noise AnalysisThis paper presents an analysis of the slat noise for Hybrid Wing Body (HWB) aircraft, based on a database from a 3% scale wind tunnel test. It is shown that the HWB slats are one of the dominant noise components, characterized by its broad spectral shape with a peak frequency that depends on both the mean flow velocity and the aircraft angle of attack, the former following the conventional Strouhal number scaling and the latter explainable by the dependence of the coherence length of the slat unsteady flows on the aircraft angle of attack. While the overall levels of the slat noise are shown to approximately follow the fifth power law in the flow Mach number, the effects of the Mach number manifest themselves in the noise spectra in both the amplitude and the spectral shape. The slat noise amplitude is shown to also depend on the angle of attack, assuming a minimum in the range of 3 to 5 degrees and increasing when the angle of attack moves away from this range. These features are all modeled and incorporated in slat noise prediction methodologies, extending the prediction capability from conventional aircraft designs to HWB configurations. Comparisons between predictions and data show very good agreements both in various parametric trends and in the absolute levels. The HWB aircraft is designed to operate at angles of attack much higher than those of conventional aircraft. This is shown to significantly increase the HWB slat noise. To further illustrate, the test data are extrapolated to full scale and compared with the slat noise of the Boeing 777 aircraft, showing that the former is higher the latter.
Document ID
20130003186
Acquisition Source
Langley Research Center
Document Type
Conference Paper
Authors
Guo, Yueping
(Boeing Research and Technology Huntington Beach, CA, United States)
Brunsniak, Leon
(Boeing Commercial Airplane Co. Everett, WA, United States)
Czech, Michael
(Boeing Commercial Airplane Co. Everett, WA, United States)
Thomas, Russell H.
(NASA Langley Research Center Hampton, VA, United States)
Date Acquired
August 27, 2013
Publication Date
January 7, 2013
Subject Category
Acoustics
Report/Patent Number
NF1676L-14747
AIAA Paper 2013-0462
Meeting Information
Meeting: 51st AIAA Aerospace Sciences Meeting
Location: Grapevine, TX
Country: United States
Start Date: January 7, 2013
End Date: January 10, 2013
Sponsors: American Inst. of Aeronautics and Astronautics, American Inst. of Aeronautics and Astronautics
Funding Number(s)
CONTRACT_GRANT: NNL04AA11B
TASK: NNL10AA71T
WBS: WBS 699959.02.10.07.05
Distribution Limits
Public
Copyright
Public Use Permitted.
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