An Active Liner System for Jet Engine Exhaust Silencers. Phase 1.

Abstract

In the framework of the U.S. Air Force's Advanced Technology Active Noise Reduction Initiative - an experimental program was carried out to demonstrate the feasibility of a new concept of an Active Liner. Using a 1:4 scale model of a jet engine test cell augmenter 8 dB to 15 dB reduction of the low frequency (8 Hz to 80 Hz at full scale) was obtained by inserting one or two active liner segments into a typical lined augmenter. The topics covered in this report include: (1) problems caused by low frequency noise and their land use implications, (2) description of the active liner concept, (3) control strategies employed, (4) description of the model-scale augmenter including passive and active sections and the feedback control system, (5) experimental results, (6) full-scale ramifications and (7) risk assessment of full-scale implementation.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1994
Accession Number
ADA293277

Entities

People

  • Istvan L. Ver
  • Michael Dignan

Organizations

  • BBN Technologies

Tags

Communities of Interest

  • Air Platforms
  • Biomedical
  • Human Systems
  • Sensors

DTIC Thesaurus Topics

  • Air Force
  • Air Force Facilities
  • Bandwidth
  • Boundary Layer
  • Control Systems
  • Engines
  • Exhaust Gases
  • Feedback
  • Frequency
  • High Temperature
  • Jet Engine Exhaust
  • Jet Engines
  • Multiple Input Multiple Output
  • Scale Models
  • Sound Pressure
  • Test Facilities
  • Wind Tunnels

Readers

  • Aerospace Engineering
  • Radar Systems Engineering.
  • ballistics.