期刊
COMBUSTION AND FLAME
卷 193, 期 -, 页码 491-501出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.combustflame.2018.04.008
关键词
Dimethoxymethane; Low-temperature oxidation; Jet-stirred reactor; Kinetic model; Photoionization molecular-beam mass spectrometry
类别
资金
- National Natural Science Foundation of China [91741109, 91541113]
- CAPRYSSES project - ANR through the PIA (Programme d'Investissement d'Avenir) [ANR- 11-LABX-006-01]
- U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES) [DE-NA0003525]
- U.S. Department of Energy's National Nuclear Security Administration [DE-NA0003525]
- DOE Office of Science User Facility [DE-AC02-05CH11231]
Dimethoxymethane (DMM, CH3OCH2OCH3) is a practical diesel additive, as well as a simple homologue in the class of polyoxymethylene dimethyl ethers (POMDMEs) which are considered as promising alternative fuels. To acquire an in-depth knowledge of DMM oxidation kinetics, the chemistry of an externally heated fuel-lean (phi = 0.5) DMM/O-2/Ar mixture was investigated in a jet-stirred reactor (JSR) operated at near atmospheric pressure (750 Torr). A molecular-beam mass spectrometer (MBMS) employing synchrotron photoionization was used to probe reactive intermediates. High-pressure (10 atm) oxidation experiments covering different equivalence ratios (0.2, 0.5 and 1.5) were carried out using another JSR facility equipped with gas chromatography (GC) and Fourier transform infrared spectrometry (FTIR) for speciation measurements. A new kinetic model was constructed and validated against the current measurements as well as those reported in literature. No obvious low-temperature reactivity was observed for DMM under the investigated conditions, though DMM has a long enough chain to allow internal hydrogen transfers leading to chain-branching. The kinetic modeling showed that hydrogen abstractions from the central (-OCH2O-) moiety are favored, producing dominantly the CH3OCHOCH3 fuel radical, which then rapidly decomposes instead of leading to chain-branching via O-2 addition. In contrast, the minor fuel radical CH3OCH2OCH2 can go through the O-2 addition and the subsequent isomerization steps, as confirmed by the detection of cyclic ether species. Another impact of the fast CH3 production from CH3OCHOCH3 beta-scission is that CH3O2H serves as an important OH provider, facilitating the fuel consumption at medium temperatures. Major fuel destruction patterns could also apply to larger POMDME compounds. (C) 2018 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据