Accession Number:

ADA270720

Title:

Detailed Structure Study of an H2/N2O/Ar Flame Employing Molecular Beam Mass Spectrometry, Laser Spectroscopy, and Modeling

Descriptive Note:

Final rept. Jun 1992-Jan 1993

Corporate Author:

ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD

Report Date:

1993-10-01

Pagination or Media Count:

61.0

Abstract:

A combined experimental and detailed chemical modeling study has been performed on a 20-torr, stoichiometric H2N2OAr burner stabilized flame. This study provides a check of part of the mechanism to be used in models for the combustion of solid nitramine propellants. Species concentration profiles were measured using molecular beam sampling with mass spectrometric detection and laser-induced fluorescence, while temperature profiles were measured with coated PtPt-Rh10 thermocouples. The burned gases of the flame contain about 2 mole of NO and H2, a concentration of approximately 10 times more than that of their equilibrium. This formation prevents full energy release of the systems within or near the flame zone. Experimental flame profiles of the major species, H2, N2O, N2, and H2O, as well as the minor species, NO, O2, OH, H, O, and NH, are presented and compared to calculated profiles generated by PREMIX, a one- dimensional premixed laminar flame code. The chemical mechanism used in the flame code was derived from a critical literature review and consists of 38 reactions and 14 species. Rate and sensitivity analyses performed reveal the intricacies of the mechanism as well as reactions important in the modeling of the experimental results. Several key reactions, including N2OHHO2N2NONH, whose rate coefficients have been controversial, are discussed in detail. In addition, the importance of various collision partners in the key initiation step, N2O MN2OM, is presented and discussed.

Subject Categories:

  • Inorganic Chemistry
  • Physical Chemistry
  • Atomic and Molecular Physics and Spectroscopy
  • Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE