Accession Number : ADA017672

Title :   Combustion Generated Noise in Turbopropulsion Systems.

Descriptive Note : Final technical rept. Jun 72-May 75,

Corporate Author : GEORGIA INST OF TECH ATLANTA SCHOOL OF AEROSPACE ENGINEERING

Personal Author(s) : Strahle,Warren C. ; Muthukrishnan,M. ; Handley,John C.

Report Date : JUL 1975

Pagination or Media Count : 66

Abstract : The results are presented of a three year program investigating direct combustion noise in hydrocarbon-air flames. Tasks completed during the final year of the program have been (1) the use of an exterior facility to investigate the noise from a large, 2 inch diameter burner and (2) the use of the anechoic facility to test flames stabilized by bluff body flameholders. Emphasis in the program has been on premixed, fuel lean turbulent flames using ethylene, acetylene, propane and propylene fuels with air as the oxidizer. Conclusions of practical interest are (1) combustion noise can be an important contributor to the overall noise problem from turbopropulsion systems if the system extracts high shaft power, (2) it is not important to the nosie problem from afterburning turbopropulsion systems, (3) if the noise output of a particular combustor type is known in one installation, valid predictions may be made for the noise output of the same type of combustor in a different installation and (4) combustion noise may be a contributor to the afterburner instability problem. (Author)

Descriptors :   *Combustion, *Noise reduction, *Flames, *Noise generators, Afterburners, Oxidizers, Quiet, Turbulence, Aircraft, Broadband

Subject Categories : Aircraft
      Countermeasures
      Combustion and Ignition

Distribution Statement : APPROVED FOR PUBLIC RELEASE