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OverviewAn experiment to measure the noise shielding of the blended wing body design concept was developed using a simplified wedge-shaped airframe. The experimental study was conducted in the Langley Anechoic Noise Research Facility. A wideband, omnidirective sound source in a simulated engine nacelle was held at locations representative of a range of engine locations above the wing. The sound field around the model was measured with the airframe and source in place and with source alone, using an-array of microphones on a rotating hoop that is also translated along an axis parallel to the airframe axis. The insertion loss was determined from the difference between the two resulting contours. Although no attempt was made to simulate the noise characteristics of a particular engine, the broadband noise source radiated sound over a range of scaled frequencies encompassing 1 and 2 times the blade passage frequency representative of a large, high-bypass-ratio turbofan engine. The measured data show that significant shielding of the inlet-radiated noise is obtained in the area beneath and upstream of the model. The data show the sensitivity of insertion loss to engine location. Gerhold, Carl H. and Clark, Lorenzo R. Langley Research Center NASA/TM-2001-210840, L-18053, NAS 1.15:210840 Full Product DetailsAuthor: National Aeronautics and Space Adm NasaPublisher: Independently Published Imprint: Independently Published Dimensions: Width: 21.60cm , Height: 0.20cm , Length: 27.90cm Weight: 0.109kg ISBN: 9781724112699ISBN 10: 1724112694 Pages: 36 Publication Date: 27 September 2018 Audience: General/trade , General Format: Paperback Publisher's Status: Active Availability: In stock We have confirmation that this item is in stock with the supplier. It will be ordered in for you and dispatched immediately. Table of ContentsReviewsAuthor InformationTab Content 6Author Website:Countries AvailableAll regions |