Accession Number : AD0758349

Title :   Jet Engine Burn-Through Investigation. Volume I. Sonic Analysis.

Descriptive Note : Final rept. Jun-Sep 72,

Corporate Author : MAGNAVOX CO FORT WAYNE IND FORT WAYNE DIV

Personal Author(s) : Schumacker,Richard W.

Report Date : MAR 1973

Pagination or Media Count : 80

Abstract : The work performed during this program was directed toward determining the acoustic characteristics of simulated burn-through failures. To determine the feasibility of detecting this failure acoustically two types of jet engines (J-47 and J-57) were modified to simulate burn-through failures. Magnetic tape recordings of the modified engines were made to determine the extent of the acoustic spectrum, the relationship of engine speed to failure related sound pressure levels and acoustic spectrum, the effect of sensor location to detect the failure acoustically and characteristic acoustic spectra at burn-through. The recorded data was analyzed by real time spectrum analysis and mean square techniques. Results indicated that the simulated burn-through failure acoustic spectra consists primarily of broadband random noise above 5 kHz. It was also determined that sensor location is an important factor in detecting burn-through failures. Based on the results it is concluded that acoustic detection of a burn-through failure is feasible. (Author)

Descriptors :   (*BURNTHROUGH, *ACOUSTIC DETECTORS), (*TURBOJET ENGINES, BURNTHROUGH), FAILURE(MECHANICS), MICROPHONES, MONITORS, ACOUSTIC EQUIPMENT

Subject Categories : Acoustics
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE