Accession Number:

ADA276061

Title:

Infrared Fiber Optic Diagnostic Observations of Solid Propellant Combustion

Descriptive Note:

Final rept. 21 Jan 1991-30 Sep 1993

Corporate Author:

AERODYNE RESEARCH INC BILLERICA MA

Report Date:

1993-10-01

Pagination or Media Count:

47.0

Abstract:

We report on work to develop and demonstrate a diagnostic technique using infrared fiber optics to probe the decomposition processes in burning gun propellant strands. The experiments reported here involve measuring the absorption across an open gap between two embedded fibers as it fills with gaseous decomposition products. Spectroscopic detection is achieved using pairs of bandpass filters. The absorption record can be correlated with readings from embedded thermocouples and with a high resolution video recording of the burn. We have observed N20, a decomposition product of RDX, evolving into the observation volume. The N20 appearance is often an abrupt event. Coupled with evidence that it can occur while the observation region is relatively cool and far from the burning surface observed in cases involving burning at 6 atm pressure, these observations suggest hypotheses concerning the physical processes in the condensed phases of this propellant, hypotheses including the development of pressurized voids or matrix-trapped bubbles which can release decomposition gases into the unburnt propellant through suddenly opening cracks. The appearance of N20 after the temperature record suggests that melting and decomposition of RDX have begun observed in 1 atm cases implies that N20 formation is indeed not an initial step in RDX decomposition under our conditions. Solid propellant combustion, Infrared fiber optic absorption diagnostic.

Subject Categories:

  • Ammunition and Explosives
  • Fiber Optics and Integrated Optics
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE