Accession Number:

ADA214891

Title:

Deuterium Isotope Effects During HMX Combustion: Chemical Kinetic Burn Rate Control Mechanism Verified

Descriptive Note:

Journal article

Corporate Author:

FRANK J SEILER RESEARCH LAB UNITED STATES AIR FORCE ACADEMY CO

Report Date:

1989-01-01

Pagination or Media Count:

12.0

Abstract:

The appearance of a significant deuterium isotope effect during the combustion of the solid HMX compound verifies that the chemical reaction kinetics is a major contributor in determining the experimentally observed or global burn rate. Burn rate comparison of HMX and its deuterium labeled HMX-d8 analogue reveals a primary kinetic deuterium isotope effect 1 deg. KDIE at 500 psig 3.55 MPa and 1000 psig 6.99 MPa pressure and selectively identifies covalent carbon-hydrogen bond rupture as the mechanistic step which ultimately controls the further HMX burn rate under the static combustion conditions of this experiment. The 1 deg. KDIE value further suggests the rate-limiting C-H bond rupture occurs during the solid state HMX decompositiondeflagration portion of the overall combustion event and is supported by other independently published studies. A possible anomalous KDIE result at 1500 psig 10.4 MPa is addressed. This condensed phase KDIE approach illustrates a direct link between lower temperaturepressure thermal decomposition and deflagration processes and their potential applicability to the combustion regime. Most importantly, a new general method is demonstrated for mechanistic combustion investigations which selectively permits an in-situ identification of the compounds burn rate- controlling step. Reprints. aw

Subject Categories:

  • Physical Chemistry
  • Isotopes
  • Ammunition and Explosives
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE