Supersonic Transport Noise Reduction Technology Program - Phase 2, Volume 2

Abstract

Both compressor and turbine noise were studied in the turbomachinery noise reduction areas. A 3-stage low pressure compressor with variable-flap inlet guide vanes was tested at General Electric's outdoor test site. A hybrid inlet, which employs airflow acceleration suppression in combination with wall acoustic treatment, was investigated as the suppression device for all three noise monitoring point operating conditions. The effect of auxiliary inlets on noise leakage and suppression was studied for takeoff mode. Also, variable inlet guide vane flaps were used to reduce area and generate high passage Mach numbers a another means of compressor noise suppression. Turbine noise was studied using a J85 engine with massive inlet suppressor and open nozzle to unmask the turbine. Second-stage turbine blade/nozzle spacing and exhaust acoustic treatment were investigated as means of turbine noise suppression. The best performing components from noise suppression work performed under the jet and turbomachinery noise reduction tasks were integrated into a viable-type aircraft-engine system study. Overall system noise was evaluated from EPNL estimates of the suppressed and unsuppressed SST systems relating to the current FAR Part 36 Noise Regulations.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1975
Accession Number
ADB010469

Entities

People

  • E. J. Stringas
  • J. T. Blozy
  • R. B. Mishler
  • S. B. Kazin
  • V. L. Doyle

Organizations

  • General Electric

Tags

Communities of Interest

  • Air Platforms
  • Human Systems
  • Sensors

DTIC Thesaurus Topics

  • Acoustics
  • Aerodynamic Characteristics
  • Aircrafts
  • Airframes
  • Boundary Layer
  • Fluid Dynamics
  • Jet Engine Exhaust
  • Jet Engine Noise
  • Measurement
  • Pressure Distribution
  • Pressure Measurement
  • Supersonic Transport Aircraft
  • Test And Evaluation
  • Test Facilities
  • Three Dimensional
  • Turbojet Engines
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Aerodynamics.
  • Aerospace Engineering

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flow
  • Space
  • Space - Hall-Effect Thruster