Shock-Tube Experiments and Chemical Kinetic Modeling Study of CH₄ Sensitized by CH₃NHCH₃

Abstract

Ignition delay times of stoichiometric CH 4 /CH 3 NHCH 3 /O 2 /Ar mixtures are measured with a shock tube in the temperature range of 1100−2000 K. Different pressures (4, 8, and 18 atm) and CH 3 NHCH 3 blending ratios (0, 0.05, 0.1, 0.2, 0.5, and 1) are explored. CH 3 NHCH 3 promotes CH 4 ignition. Correlations for the measured ignition delay times are inferred through multiple linear regression. The measured ignition delay times are compared to the predictions of a recently developed CH 3 NHCH 3 kinetic model with C 0 −C 2 reaction subsets, and a new model for CH 4 /CH 3 NHCH 3 /O 2 /Ar mixtures is assembled and validated against the present measurements. To elucidate the effect of CH 3 NHCH 3 on CH 4 ignition, kinetic analyses including sensitivity and rate of production are performed. Perturbation of the radical pool (H, CH 3 , OH, and HO 2 ) leading to the observed effects is discussed.

Product Detection of the CH Radical Reactions with Ammonia and Methyl-Substituted Amines

“…Ammonia and its amine derivatives are emitted as gases in the atmosphere from a variety of sources such as biomass burning, vegetation, and combustion, as well as industry. , These nitrogen-containing molecules are of special interest in combustion environments where they impact the oxidation and ignition of hydrocarbon fuels. , In addition, their chemistry in reactive carbon-rich environments may play a significant role in the formation of NO x . − An improved utilization of biomass-derived nitrogen-containing compounds as fuels and a better understanding of the role of amines in combustion both require a systematic study of the chemistry of ammonia and substituted amines with combustion-relevant radicals.…”