HIGH VELOCITY JET NOISE SOURCE LOCATION AND REDUCTION. TASK 3. EXPERIMENTAL INVESTIGATION OF SUPPRESSION PRINCIPLES VOLUME II. PARAMETRIC TESTING AND SOURCE MEASUREMENTS

Experimental investigations were conducted of suppression principles, including developing an experimental data base, developing a better understanding of jet noise suppression principles, and formulating empirical methods for the acoustic design of jet noise suppressors. Acoustic scaling has been experimentally demonstrated, and five 'optimum' nozzles have been selected for subsequent anechoic free-jet testing. A series of experimental tests was conducted to provide farfield acoustic data on 47 baseline and suppressor nozzle configurations and to provide aerodynamic nozzle performance on 18 of the configurations. Suppressor design parameters evaluated experimentally included: suppressor area ratio, radius ratio, flow management, inner stream geometry, element number and type, treated ejectors on multielement and unsuppressed inverted-coannualar-flow nozzles. Parametric testing established suppression levels for single and dual flow nozzles during static operation. Selective free-jet tests conducted on eight configurations were utilized to establish flight suppression levels for plug, chute, tube and hole nozzles. The aerodynamic performance test program illustrated that suppressed exhaust nozzles which incorporate elemental base areas as an integral part of the design are sensitive to external Mach number. In general suppressor element base drag was the most significant loss mechanism. This volume is part of the four volume set that constitutes the Task 3 final report.

• Supplemental Notes:
  • See also Task 3, Volume 3, AD-A094 295.
• Corporate Authors:

  General Electric

  Marine Turbine & Gear Engineer, 1100 Western Ave
  Lynn, MA  United States  01910

  Federal Aviation Administration

  800 Independence Avenue, SW
  Washington, DC  United States  20591
• Authors:
  • Brausch, J F
  • Clapper, W S
  • Scott, P F
  • SMITH, M A
  • Stringas, E J
• Publication Date: 1978-12

Media Info

• Pagination: 869 p.

Subject/Index Terms

• TRT Terms: Acoustic measuring instruments; Acoustics; Aircraft noise; Data collection; Databases; Exhaust gases; Far field; Flow; Jet engines; Noise control; Nozzles; Optimization; Plugs (Fillers); Plumes; Scaling factor; Static tests; Suppressors; Velocity
• Uncontrolled Terms: High velocity; Noise reduction; Parameters; Sources
• Old TRIS Terms: Acoustic data; Acoustic measurement; Exhaust nozzles; Jet engine noise; Jet flow; Nozzle area ratio; Nozzle gas flow; Variable area nozzles
• Subject Areas: Environment; Vehicles and Equipment;

Filing Info

• Accession Number: 00328894
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: R78AEG627-VOL-2, FAA-RD-76-79-3-2
• Contract Numbers: DOT-OS-30034
• Files: NTIS, USDOT
• Created Date: May 21 2003 12:00AM