The combustion kinetics of methyl formate (MeFo), a promising oxygenated, highly knock-resistant e-fuel, is investigated in this work. The potential energy surfaces (PESs) of the low-temperature oxidation reactions of MeFo radicals were determined at the CCSD(T)-F12/cc-pVTZ-F12//B2PLYP-D3/cc-pVTZ level of theory and their rate coefficients were obtained with RRKM/master equation. The thermochemical properties of relevant intermediate species were calculated by using the G4 method. A chemical mechanism for the oxidation of MeFo was developed by adding fuel-specific reactions taken from a literature model into a well-validated base mechanism, and incorporating the newly calculated rate constants of elementary reactions and thermochemical properties of species. The fuel-specific mechanism was further revised in terms of reaction channels and rate coefficients for improved prediction accuracy. In particular, the ${\mathrm{O}}_2$ addition to hydroperoxy radicals (QOOH), the isomerization of peroxy hydroperoxy radicals (OOQOOH), the subsequent ketohydroperoxide (KET) decomposition, and the formally direct pathways of MeFo radicals (R) with ${\mathrm{O}}_2$ were added for the completeness of consumption pathways, in conjunction with the reaction channels of alkoxy radicals (RO) and hydroperoxides (ROOH). For good model prediction accuracy of ignition delay times, especially in the high-temperature range, the resulting mechanism was optimized by modifying the rate constants of several important H-atom abstraction reactions of MeFo within their uncertainty limits. The performance of the proposed mechanism is demonstrated through extensive validation against literature data obtained from different experimental configurations. Finally, the underlying reaction pathways of MeFo are explored by means of reaction flux analysis with the newly developed chemical mechanism.

Novelty and significance statement: This work proposes a new reaction kinetic mechanism for the oxidation of methyl formate. Quantum chemistry calculation at high level of theory was performed to explore the low-temperature chemistry of MeFo. The reaction mechanism was improved by including missing reaction channels, incorporating theoretically calculated rate and thermochemical data, and modifying rate constants of sensitive reactions. The mechanism has been validated successfully against extensive data available in the literature covering a wide range of conditions and facilities. By using this new mechanism, reaction pathway analysis is performed to provide insights into the oxidation chemistry of MeFo.

这项工作对甲酸甲酯 (MeFo) 的燃烧动力学进行了研究，这是一种很有前途的含氧、高度抗爆的电子燃料。在CCSD(T)-F12/cc-pVTZ-F12//B2PLYP-D3/cc-pVTZ理论水平上测定了MeFo自由基低温氧化反应的势能面(PES)，其速率系数为通过 RRKM/主方程获得。采用G4方法计算了相关中间物种的热化学性质。通过将文献模型中的燃料特定反应添加到经过充分验证的基本机制中，并结合新计算​​的基元反应速率常数和物质的热化学性质，开发了 MeFo 氧化的化学机制。在反应通道和速率系数方面进一步修改了燃料特定机制，以提高预测精度。特别是，${\mathrm{氧}}_2$除了氢过氧自由基（QOOH）之外，过氧氢过氧自由基（OOQOOH）的异构化，随后的酮氢过氧化物（KET）分解，以及MeFo自由基（R）与${\mathrm{氧}}_2$添加了烷氧基自由基（RO）和氢过氧化物（ROOH）的反应通道，以实现消耗途径的完整性。为了获得点火延迟时间的良好模型预测精度，特别是在高温范围内，通过在不确定性限度内修改 MeFo 的几个重要的 H 原子提取反应的速率常数来优化所得机制。通过对从不同实验配置获得的文献数据进行广泛验证，证明了所提出机制的性能。最后，通过反应通量分析和新开发的化学机理探索了MeFo的潜在反应途径。

新颖性和意义陈述：这项工作提出了甲酸甲酯氧化的新反应动力学机制。通过高理论水平的量子化学计算，探索MeFo的低温化学性质。通过包含缺失的反应通道、结合理论计算的速率和热化学数据以及修改敏感反应的速率常数来改进反应机理。该机制已根据文献中涵盖各种条件和设施的大量数据成功得到验证。通过使用这种新机制，进行反应途径分析，以深入了解 MeFo 的氧化化学。