Comparison between design and installed acoustic characteristics of NASA Lewis 9- by 15-foot low-speed wind tunnel acoustic treatment [PDF]
The test section of the NASA Lewis 9- by 15-Foot Low-Speed Wind Tunnel was acoustically treated to allow the measurement of sound under simulated free-field conditions.
Dahl, Milo D., Woodward, Richard P.
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Audiology: Communication ResearchRESUMO Objetivo: Caracterizar os valores de reflectância e absorvância de banda larga em lactentes com integridade de orelha média. Métodos: Foram analisados os valores de reflectância e absorvância de banda larga, para os estímulos chirp e tom puro ...
Priscila Pereira dos Santos +4 more
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Development and testing of cabin sidewall acoustic resonators for the reduction of cabin tone levels in propfan-powered aircraft [PDF]
The use of Helmholtz resonators to increase the sidewall transmission loss (TL) in aircraft cabin sidewalls is evaluated. Development, construction, and test of an aircraft cabin acoustic enclosure, built in support of the Propfan Test Assessment (PTA ...
Balena, F. J. +3 more
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Development of modified vibration test criteria for qualifying space vehicle components [PDF]
The results of the evaluation of two response prediction methods relating to the prediction of structural responses of stiffened shell structures with or without attached components, and subjected to broadband acoustic excitations are presented.
Chang, K. Y., Kao, G. C.
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Developmental design, fabrication, and test of acoustic suppressors for fans of high bypass turbofan engines [PDF]
An analysis procedure was developed for design of acoustically treated nacelles for high bypass turbofan engines. The plan was applied to the conceptual design of a nacelle for the quiet engine typical of a 707/DC-8 airplane installation.
Gregg, G. E. +3 more
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, 2012 GoreTM PolarchipTM heat insulating Teflon and Dow ChemicalsTM Voracor CS Polyurethane were characterized in this study by conducting compression tests at various strain rates. Quasi-static compression tests were done with a Shimadzu AG-X conventional test machine while two different modified Split Hopkinson Pressure Bar (SHPB) systems were used for ...
openaire +3 more sources
Design of an Advanced Inlet Liner for the Quiet Technology Demonstrator 3 [PDF]
The utilization of advanced fan designs (including higher bypass ratios) and shorter engine nacelles has highlighted a need for increased fan noise reduction over a broad frequency range.
Jones, Michael G., Nark, Douglas M.
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Spinning mode sound propagation in ducts with acoustic treatment [PDF]
A detailed theoretical study of the acoustic propagation of spinning modes in acoustically treated open circular ducts is described. The suppressor with splitter rings was modeled by using the rectangular approximation to the annular duct.
Rice, E. J.
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RUDN Journal of Medicine, 2011 We have examined 72 patients aged from 18 till 62 with cerebral and cerebrospinal multiple sclerosis (MS) form. All patients have been underwent оtoneurologiс examination, electronystagmography (ENG), caloric tests, pure-tone audiometry, high frequency ...
I M Kirichenko +5 more
doaj
Design integration and noise studies for jet STOL aircraft. Task 7C: Augmentor wing cruise blowing valveless system. Volume 1: Static testing of augmentor noise and performance [PDF]
Static performance and acoustic tests were conducted on a two-dimensional one-third-scale augmentor flap model that simulated a cruise blowing augmentor system designed for a scale augmentor flap model that simulated a cruise blowing augmentor, which ...
Campbell, J. M. +2 more
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