APPLICATION OF EXTENDED PLUG NOZZLE NOISE SUPPRESSION THEORY TO A SMALL TURBOJET ENGINE.

Abstract

Small scale tests showed the best overall results when: (1) The area of the plug equals the annular flow area between the plug and nozzle. (2) A plug length ranging from zero to two nozzle diameters before the start of the termination. (3) A plug termination of a 10 degree straight taper. This configuration reduced the noise by about 10 db at a pressure ratio of 3.0 with a corresponding thrust loss of about 6%. On the WR2-2 turbojet engine, the extended plug nozzle similarly reduced exhaust noise although to a smaller extent. A 3 db reduction in noise was achieved with a corresponding thrust loss of 4%, however, the engine was only operated up to an exhaust pressure ratio of 2.5. Another nozzle showed a 1 1/2 db reduction with a corresponding thrust increase of 5%. The extended plug nozzle approach to jet noise suppression shows promise. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 07, 1965
Accession Number
AD0645978

Entities

People

  • H. B. Moore
  • J. M. Clinch

Organizations

  • Williams International

Tags

DTIC Thesaurus Topics

  • Annular Flow
  • Diameters
  • Engines
  • Flow
  • Jet Aircraft
  • Nozzles
  • Plug Nozzles
  • Turbojet Engines

Readers

  • Aerodynamics.
  • Aerospace Engineering
  • Phased Array Antenna Design.