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System Noise Assessment of Blended-Wing-Body Aircraft With Open Rotor PropulsionAn aircraft system noise study is presented for the Blended-Wing-Body (BWB) aircraft concept with three open rotor engines mounted on the upper surface of the airframe. It is shown that for such an aircraft, the cumulative Effective Perceived Noise Level (EPNL) is about 24 dB below the current aircraft noise regulations of Stage 4. While this makes the design acoustically viable in meeting the regulatory requirements, even with the consideration of more stringent noise regulations of a possible Stage 5 in the next decade or so, the design will likely meet stiff competitions from aircraft with turbofan engines. It is shown that the noise levels of the BWB design are held up by the inherently high noise levels of the open rotor engines and the limitation on the shielding benefit due to the practical design constraint on the engine location. Furthermore, it is shown that the BWB design has high levels of noise from the main landing gear, due to their exposure to high speed flow at the junction between the center body and outer wing. These are also the reasons why this baseline BWB design does not meet the NASA N+2 noise goal of 42 dB below Stage 4. To identify approaches that may further reduce noise, parametric studies are also presented, including variations in engine location, vertical tail and elevon variations, and airframe surface acoustic liner treatment effect. These have the potential to further reduce noise but they are only at the conceptual stage.
Document ID
20160005907
Acquisition Source
Langley Research Center
Document Type
Conference Paper
Authors
Guo, Yueping
(Boeing Research and Technology Huntington Beach, CA, United States)
Thomas, Russell H.
(NASA Langley Research Center Hampton, VA, United States)
Date Acquired
May 6, 2016
Publication Date
January 5, 2015
Subject Category
Acoustics
Report/Patent Number
NF1676L-20542
Meeting Information
Meeting: AIAA SciTech 2015
Location: Orlando, FL
Country: United States
Start Date: January 5, 2015
End Date: January 8, 2015
Sponsors: American Inst. of Aeronautics and Astronautics
Funding Number(s)
WBS: WBS 699959.02.07.07.08
Distribution Limits
Public
Copyright
Public Use Permitted.
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