NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Sound power spectrum and wave drag of a propeller in flightTheory is presented for the sound power and sound power spectrum of a single rotation propeller in forward flight. Calculations are based on the linear wave equation with sources distributed over helicoidal surfaces to represent effects of blade thickness and steady loading. Sound power is distributed continuously over frequecy, as would be expected from Doppler effects, rather than in discrete harmonics. The theory is applied to study effects of sweep and Mach number in propfans. An acoustic efficiency is defined as the ratio of radiated sound power to shaft input power. This value is the linear estimate of the effect of wave drag due to the supersonic blade section speeds. It is shown that the acoustic efficiency is somewhat less than 1 percent for a well designed propfan.
Document ID
19890046353
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Hanson, D. B.
(United Technologies Corp. Hamilton Standard Div., Windsor Locks, CT, United States)
Date Acquired
August 14, 2013
Publication Date
April 1, 1989
Subject Category
Acoustics
Report/Patent Number
AIAA PAPER 89-1081
Accession Number
89A33724
Funding Number(s)
CONTRACT_GRANT: NAS3-23720
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available