Analysis of Safety and Performance Status of Double-Base Propellants by Heat Flow Calorimetry
Abstract
Thermo-kinetic oscillations are among the most fascinating chemical oscillation reactions known in a system where significant temperature/pressure oscillations occur. The transport of heat out of the system is an essential part of the mechanism of the oscillation. The reaction causes the temperature/pressure to rise, and the rising temperature/pressure exerts a feed-back inhibition on the reaction to generate a feed-back loop (oscillation). An oscillation phenomenon was observed during the microcalorimetric evaluation of 20 mm gun propellant. The heat flow began to gradually start a sinusoidal type oscillation after approximately 105 days of aging at 80 deg C (~ 70% decomposition). The system resembles the Lotka model from 1910 with the variation that the autocatalytic reaction is substituted by a reaction with thermic acceleration, and the reaction which removes the autocatalytic substance is substituted by the transport of heat out of the system. The pattern of the oscillation is affected by internal gas pressure which is a function of the free head space of the test ampule. A possible similarity of the oscillation is suggested to the time-to-fume as determined by the NATO 65.5 deg C thermal stability tests used in other 20 mm propellants. The scope of this paper is limited to a discussion of the relationship between the "time-to-oscillation" and the "time-to-fume" during the accelerated aging of 20 mm gun propellant.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1998
- Accession Number
- ADA497911
Entities
People
- Anton Chin
- Daniel S. Ellison
Organizations
- Naval Surface Warfare Center