Abstract
Despite considerable achievements of combustion kinetics, the chemical kinetic impacts of trace promoting species on practical fuel combustion has been hitherto handled seperately either as ignition or extinction-related effects, overlooking the impact of the extinction process on re-ignition kinetics. We herein demonstrate the applicability of oscillatory stirred reactor configuration to quantify the combined impacts of the methyl radical on ignition/extinction of primary reference fuels (PRF) in stoichiometric and ultra-lean conditions, thereby complementing steady-state configurations for kinetic mechanism validation. A new convenient reactivity metric is proposed based on the matching of temperature Fourier spectrum of additivated fuels with corresponding PRF. Using a new skeletal mechanism obtained from calibration on a variety of ignition experiments, we characterize ignition regimes by CEMA analysis and highlight the key reactions of the C 1 -C 3 reaction subsets that should be included in minimal skeletal mechanisms used in reactive CFD modeling to properly describe re-ignition phenomena over a variety of new combustion applications involving methyl radical injection. (c) 2021 The Combustion Institute. Published by Elsevier Inc. All rights reserved.