An experimental and modeling study on the low temperature oxidation of surrogate for JP-8 part I: Neat 1,3,5-trimethylbenzene

This work describes the experimental and modeling study of low temperature oxidation of 1,3,5-trimethylbenzene (T135MB) in a jet-stirred reactor over the temperature range of 700-1100 K at atmospheric pressure under fuel-lean and stoichiometric conditions. 9 C-0-C-5 hydrocarbons, 6 oxygenated products and 6 aromatic compounds were identified and quantified using GC and GC-MS. A detailed kinetic based on T135MB model of Dievart et al. was proposed to simulate the low-temperature experimental results in the present work. Rate constants of T135MB decomposition and metatheses reactions were calculated with CBS-QB3 method implemented in Gaussian 09. The performance of proposed mechanism in reproducing the experimental data is reasonably good. Reaction flux analysis shows that dominant consumption channels for T135MB oxidation are H-abstraction reactions to form 3,5-dimethylbenzyl radicals, while reactions with O/OH radicals to generate 1,3,5-trimethylphenoxyl/1,3,5-trimethylphenyl and ipso-addition to form m-xylene play minor roles. Sensitivity analysis reveals that H-abstraction from side methyl groups of T135MB by OH radical is the most inhibiting reaction oxidation at Phi = 1.0, while it is a promoting reaction at Phi = 0.4. Moreover, current model were validated against experimental results on T135MB oxidation in flow reactor from Dievart et al. as well as global combustion property ignition delay times from Rao et al. and Dievart et al. with reasonable predictions. (C) 2018 The Combustion Institute. Published by Elsevier Inc. All rights reserved.