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Accession Number N20120012880
Title Low-Speed Fan Noise Attenuation from a Foam-Metal Liner.
Publication Date Jan 2011
Media Count 15p
Personal Author D. L. Sutliff M. G. Jones
Abstract A foam-metal liner for attenuation of fan noise was developed for and tested on a low-speed fan. This type of liner represents a significant advance over traditional liners, due to the possibility of placement in close proximity to the rotor. An advantage of placing treatment in this region is that the acoustic near field is modified, thereby inhibiting the noise-generation mechanism. This can result in higher attenuation levels than could be achieved by liners located in the nacelle inlet. In addition, foam-metal liners could potentially replace the fan rub strip and containment components, ultimately reducing engine components and thus weight, which can result in a systematic increase in noise reduction and engine performance. Foam-metal liners have the potential to reduce fan noise by 4 dB based on this study.
Keywords Aerodynamic noise
Engine parts
Fan blades
Low speed
Metal foams
Noise generators
Noise reduction
Sound fields

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 46A - Acoustics
51A - Aerodynamics
Corporate Author National Aeronautics and Space Administration, Cleveland, OH. NASA John H. Glenn Research Center at Lewis Field.
Document Type Journal article
Title Note N/A
NTIS Issue Number 1303
Contract Number N/A

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