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Accession Number N20120014314
Title Acoustic Measurements of an Uninstalled Spacecraft Cabin Ventilation Fan Prototype.
Publication Date Aug 2012
Media Count 20p
Personal Author C. A. Brown D. M. Podboy J. Winkel J. H. Mirecki J. S. Kolacz L. D. Koch R. A. Loew T. D. Shook
Abstract Sound pressure measurements were recorded for a prototype of a spacecraft cabin ventilation fan in a test in the NASA Glenn Acoustical Testing Laboratory. The axial fan is approximately 0.089 m (3.50 in.) in diameter and 0.223 m (9.00 in.) long and has nine rotor blades and eleven stator vanes. At design point of 12,000 rpm, the fan was predicted to produce a flow rate of 0.709 cu m/s (150 cfm) and a total pressure rise of 925 Pa (3.72 in. of water) at 12,000 rpm. While the fan was designed to be part of a ducted atmospheric revitalization system, no attempt was made to throttle the flow or simulate the installed configuration during this test. The fan was operated at six speeds from 6,000 to 13,500 rpm. A 13-microphone traversing array was used to collect sound pressure measurements along two horizontal planes parallel to the flow direction, two vertical planes upstream of the fan inlet and two vertical planes downstream of the fan exhaust. Measurements indicate that sound at blade passing frequency harmonics contribute significantly to the overall audible noise produced by the fan at free delivery conditions.
Keywords Acoustic measurement
Aerodynamic noise
Fan blades
Flow velocity
Frequencies
Harmonics
Pressure measurement
Sound pressure
Stators
Vanes
Ventilation fans


 
Source Agency National Aeronautics and Space Administration
NTIS Subject Category 46A - Acoustics
95D - Human Factors Engineering
84C - Manned Spacecraft
Corporate Author National Aeronautics and Space Administration, Cleveland, OH. NASA John H. Glenn Research Center at Lewis Field.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1307
Contract Number N/A

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