Studies of the combustion of dimethyl hydrazine and related compounds

Abstract

Spontaneous ignition studies are here reported on hydrazine and (unsymmetrical) dimethyl hydrazine. This paper is part of a general program on the combustion of endothermic fuels. o 1. Hydrazine systems: N 2 H 4 +NO; N 2 H 4 +N 2 O. The work on hydrazine concerns the N 2 H 4 +NO and N 2 H 4 +N 2 O systems. Particular aims are to establish the modes of reaction, to investigate the critical conditions for ignition, and to investigate the possible thermal character of the explosion. In mixtures with nitric oxide there is either slow reaction or explosion. The stoichiometric mixture (N 2 H 4 +2NO) is the most ignitible. The influence of inert diluents and comparison with N 2 H 4 +O 2 suggests that explosion is thermal in character. The ready ignition is correlated with the postulated reactivity of nitric oxide towards radicals such as NH and NH 2 . In mixtures with nitrous oxide, explosion, appears to be initiated as if nitrous oxide were merely a diluent although, the nitrous oxide does not survive the flame. o 2. Dimethyl hydrazine systems: Me 2 NNH 2 +O 2 . There is very little previous published work on dimethyl hydrazine (DMH) combustion. The conditions for DMH to undergo spontaneous ignition both in decomposition and in oxidative combustion have been examined. Distinct modes of oxidation exist. They include strong explosions, weak ignition, chemiluminescent oxidation, and slow reaction; in addition, multipe ignitions have been observed. Qualitatively, the combustion differs markedly from that of the superficially analogous mono-, di-, and trimethyl amines although there are resemblances to the ethylamines.