An intermediate temperature modeling study of the combustion of neopentane

Low temperature hydrocarbon fuel oxidation proceeds via straight and branched chain reactions involving alkyl and alkyl peroxy radicals. These reactions play a critical role in the chemistry leading to knock or autoignition in spark ignition engines. As part of an on-going study in the understanding of low temperature oxidation of hydrocarbon fuels, the authors have investigated neopentane oxidation. A detailed chemical kinetic reaction mechanism is used to study the oxidation of neopentane in a closed reactor at 500 Torr pressure, and at a temperature of 753 K when small amounts of neopentane are added to slowly reacting mixtures of H{sub 2} + O{sub 2} + N{sub 2}. The major primary products formed in the experiments included isobutene, 3,3-dimethyloxetan, acetone, methane and formaldehyde. The major secondary products were, 2,2-dimethyloxiran, propene, isobuteraldehyde, methacrolein, and 2-methylprop-2-en-1-ol. It was found that the current model was able to explain both primary and secondary product formation with a high degree of accuracy. Furthermore, it was found that almost all secondary product formation could be explained through the oxidation of isobutene--a major primary product.

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