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Effect of Operating Conditions on Gearbox Noise
NASA Technical Memorandum 105331; AVSCOM Technical Report 91—C-031
  • Fred B. Oswald, NASA Lewis Research Center
  • James J. Zakrajsek, NASA Lewis Research Center
  • Dennis P. Townsend, NASA Lewis Research Center
  • William Atherton, Cleveland State University
  • Hsiang Hsi Lin, Memphis State University
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Low-contact-ratio spur gears were tested in the NASA gear noise rig to study the noise radiated from the top of the gearbox. The measured sound power from the gearbox top was obtained from a near-field acoustic intensity scan taken at 63 nodes just above the surface. The sound power was measured at a matrix of 45 operating speeds and torque levels. Results are presented in the form of a spectral speed map and as plots of sound power versus torque (at constant speed) and as sound power versus speed (at constant torque) Because of the presence of vibration modes, operating speed was found to have more impact on noise generation than torque level. A NASA gear dynamics code was used to compute the gear tooth dynamic overload at the same 45 operating conditions used for the experiment. Similar trends were found between the analytical results for dynamic tooth overload and experimental results for sound power. Dynamic analysis may be used to design high-quality gears with profile relief optimized for minimum dynamic load and noise.

Prepared for the Sixth International Power Transmission and Gearing Conference sponsored by the American Society of Mechanical Engineers Phoenix, Arizona, September 13-16, 1992
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Fred B. Oswald, James J. Zakrajsek, Dennis P. Townsend, William Atherton, et al.. "Effect of Operating Conditions on Gearbox Noise" NASA Technical Memorandum 105331; AVSCOM Technical Report 91—C-031 (1992) p. 1 - 8
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