Far Field Noise Generation by Coaxial Flow Jet Exhausts. Volume 1. Detailed Discussion

Abstract

Model scale air jets were used in an anechoic room to conduct a parametric study on the sound produced by coaxial circular jets. The results from these model tests were analyzed and scaled to give the overall sound power output, directivity indices and the sideline sound pressure spectra and perceived noise levels for engine thrusts ranging from 10,000 pounds to 80,000 pounds. The results were used to determine the reduction in overall sound power and maximum sideline perceived noise level as a function of the ratio of the secondary nozzle area to primary nozzle area and the ratio of secondary velocity to primary velocity.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1971
Accession Number
AD0743707

Entities

People

  • Kenneth M. Eldred

Tags

Communities of Interest

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

DTIC Thesaurus Topics

  • Acoustic Impedance
  • Acoustics
  • Aircrafts
  • Atmospheric Attenuation
  • Boundary Layer
  • Computer Programs
  • Jet Aircraft
  • Jet Engines
  • Measurement
  • Noise Reduction
  • Operating Systems
  • Plastic Explosives
  • Pressure Measurement
  • Pressure Transducers
  • Sound Pressure
  • Transport Aircraft
  • Turbojet Engines

Readers

  • Acoustics.
  • Combustion and Flow Dynamics.