DETAILED KINETIC MODELING OF TOLUENE COMBUSTION

A detailed chemical kinetic mechanism for the combustion of toluene ha s been assembled and evaluated for a wide range of combustion regimes. The latter include counterflow diffusion flames, plug dow reactors, s hock tubes and premixed flames. The reaction mechanism features 743 el ementary reactions and 141 species and represents an attempt to develo p a chemical kinetic mechanism applicable to intermediate and high tem perature oxidation. Toluene thermal decomposition and radical attack r eactions leading to oxygenated species are given particular attention. The benzyl radical sub-mechanism is expanded to include izomerization and thermal decomposition reactions, which are important at flame tem peratures, and a molecular oxygen attack path to form the benzylperoxy radical, which is found to be relevant at lower temperatures. The fin al toluene kinetic model results in excellent fuel consumption profile s in both dames and plug flow reactors and sensible predictions of the temporal evolution of the hydrogen radical and pyrolysis products in shock tube experiments. The structures of toll uene/n-heptane, toluene /n-heptane/methanol and toluene/methanol diffusion dames are predicted with reasonable quantitative agreement for major and minor species pr ofiles. Furthermore, the evolution of major and intermediate species i n plug flow reactors is well modelled and excellent laminar burning ve locity predictions have also been achieved.