Speciation and the laminar burning velocities of poly(oxymethylene) dimethyl ether 3 (POMDME3) flames: An experimental and modeling study

Poly(oxymethylene) dimethyl ethers (POMDMEs) with the general chemical formula of CH3O (CH2O)(n)CH3 (n > 1) are promising oxygenated alternative fuels with substantial soot-reduction potential. Combustion kinetics of the compound with n = 3, POMDME3 [CH3O(CH2O)(3)CH3], was investigated in the present study with combined experimental and modeling efforts. Twenty-six species, including some radicals and reactive intermediates, were identified and quantified in a low-pressure laminar premixed POMDME 3 flame with a synchrotron vacuum ultraviolet photoionization mass spectrometry. Laminar burning velocities of POMDME3/air mixtures were measured in a spherical bomb at atmospheric pressure with the equivalence ratio ranging from 0.7 to 1.6. A kinetic model aimed at interpreting the high-temperature combustion chemistry of POMDME3 was constructed and tested by all the measurements with uncertainties of both experiments and model predictions taken into consideration. In addition, model analysis of the reaction pathways was performed to reveal the consumption processes of POMDME3 and the formation mecha-nisms of some crucial intermediates. The absence of carbon-carbon (C-C) bonds in the (C-O) chain structure results in significant soot-reduction potential. Relevant reaction patterns could also apply to larger POMDME compounds. (C) 2016 by The Combustion Institute. Published by Elsevier Inc.