聚甲氧基二甲醚反应动力学及聚合度影响机理探究

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中图分类号： TK46+4 文献标志码：ADOI：10.7652/xjtuxb202508012 文章编号：0253-987X（2025）08-0122-12

Investigation on Reaction Kinetics of Polyoxymethylene Dimethyl Ethers and Influence Mechanism of Polymerization Degree

ZHOU Zijie¹，YANG Yajing²，CUI Wangl，WEI Yanju¹，LIU He1 ，LIU Shenghual （1. School of Energy and Power Engineering，Xi'an Jiaotong University，Xi'an 71o049，China; 2.School of Astronautics，Xi'an JiaotongUniversity，Xi'an 7lo049，China）

Abstract： To reveal the variation law of reaction activity of polyoxymethylene dimethyl ethers （PODE） components with different polymerization degrees and the underlying kinetic mechanisms， a reaction pathway framework applicable to a wide range of conditions is constructed to comparatively analyze the multi-component reaction kinetic behaviors of PODE. Based on the reaction mechanism of dimethoxymethane （ PODE1 ），the reaction mechanisms of PODE2 and PODE3 are developed and validated. According to the role of each elementary reaction in reaction kinetics，a unified framework for PODE reaction pathways is proposed，elucidating three source channels of PODE reactivity： the typical chain-branching reaction via primary carbon dehydrogenation followed by two oxygen additions； the chain-branching reaction resulting from the decomposition of some hydroperoxy fuel radicals into carbonyl hydroperoxides；the chainbranching reaction triggered by secondary carbon dehydrogenation and decomposition into lowerpolymerization-degree fuel radicals. Sensitivity analysis of the first-stage ignition delay time of PODE demonstrates that the constructed reaction kinetic mechanism of PODE2 and PODE3 can predict experimentally measured ignition delay times and explain the reaction kinetic behaviors of PODE. Channels 1 and 2 are common chain-branching reaction pathways for all PODE molecules， while channel 3 is unique to higher-polymerization-degree PODE and serves as an important contributor to reactivity.

Keywords： polyoxymethylene dimethyl ethers； reaction kinetics；degree of polymerization； elementary reaction

在可再生合成燃料中，醚类燃料聚甲氧基二甲醚（polyoxymethylene dimethyl ethers，PODE）分子通式为 CH3O（CH2O）nCH3 （记为 PODEn ），具有十六烷值高、含氧量高、污染物排放少的特点[1-3]，并且能较好地适配压燃式内燃机，应用前景良好[4-6]为了在实际内燃机中有效应用PODE这类新型燃料，需要构建一种贴合发动机实际运行工况的燃烧反应动力学模型。（剩余21218字）