Investigation of Gearbox Design Modifications for Reducing Helicopter Gearbox Noise

Abstract

Results presented were obtained in a continuing effort to control, through development of vibration and acoustics technology, noise produced by helicopter geared power trains. The results achieved, while not all inclusive, represent a significant step in understanding the generation of gearbox noise. Efforts undertaken, directed at both the UH-1D main and CH-47 forward rotor- drive gearboxes, included predictions of lateral natural frequency and forced response vibration characteristics of the spiral bevel gear shafts, thin-shell predictions of natural frequency and forced-response vibration characteristics of the planetary ring gear casing, general and analytical modeling of gearbox mounts and adjoining airframe structure, and collection and evaluation of existing helicopter internal noise and vibration data from helicopter manufacturers and users.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1972
Accession Number
AD0742735

Entities

People

  • Robert H. Badgley
  • Thomas Chiang

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Acoustic Frequencies
  • Acoustics
  • Aircraft Equipment
  • Aircrafts
  • Airframes
  • Computer Programs
  • Dynamic Response
  • Gear Noise
  • Helicopters
  • Mechanical Impedance
  • Noise Reduction
  • Plastic Explosives
  • Resonant Frequency
  • Sound Pressure
  • Structural Components
  • Turbines
  • Vibration

Readers

  • Structural Dynamics.
  • Systems Analysis and Design
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).