Accession Number : ADA017583

Title :   Audible and Ultrasonic Acoustic Emissions from Composite Solid Propellants.

Descriptive Note : Interim rept. Feb-Jun 75,

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

Personal Author(s) : Craig,James I. ; Strahle,Warren C. ; Palfery,John

Report Date : JUL 1975

Pagination or Media Count : 52

Abstract : An apparatus to test the audible and ultrasonic emissions from composite solid propellants was designed, constructed and checked out. Tests were conducted at 300 psia for eight aluminized HTPB-AP propellants. The tests were conducted under both nitrogen and air pressurization. For the audible emissions in the range 100 - 2500 Hz there is a marked effect of the pressurization fluid. In air the noise output is 10,000 higher than in nitrogen. There is a definite possibility that the noise output is responsible for observed chamber pressure roughness level. For the ultrasonic signal in the range 50 to 300 kHz there are strong spectral peaks observed but their origin is not clear and they do not correlate with observed deflagration behavior. For audible signals a striking effect of AFCAM aluminum coating is the reduction of signal strength.

Descriptors :   *Solid rocket propellants, *Combustion, *Acoustic emissions, Measuring instruments, Instrumentation, Test methods, Pressure, Air, Nitrogen, Aluminized propellants, Coatings, Ultrasonic radiation

Subject Categories : Test Facilities, Equipment and Methods
      Combustion and Ignition
      Solid Rocket Propellants

Distribution Statement : APPROVED FOR PUBLIC RELEASE