Abstract The self-ignition of a stoichiometric acetone−oxygen mixture diluted with argon was studied both experimentally and numerically. The experiments were performed behind reflected shock waves over a temperature range from 1280 to 1810 K at a total gas concentration of [M]50 ≈ 10−5 mol/cm3. The process was monitored by recording the signals of absorption by methyl radicals (λ = 216.5 nm) and emission from electronically excited OH* radicals (λ = 308 nm) and CO2* molecules (λ = 370 nm). Numerical simulations within the framework of various detailed kinetic mechanisms were performed to reproduce our own and published experimental data on the pyrolysis and self-ignition of acetone behind reflected shock waves, including the concentration profiles of acetone and CH3 in the ground state and electronically excited OH* and CO2*, as well as the temperature dependence of the self-ignition delay time. It has been established that various detailed kinetic mechanisms describe the kinetic characteristics of the pyrolysis of acetone in shock waves with varying degrees of accuracy. At the same time, all of them predicted the measured ignition delays within a factor of two. A sensitivity analysis showed that the reactions determining the pyrolysis of acetone produce only a slight effect on the branched-chain ignition process, so that the relevant rate constants only slightly affect the ignition delay time.

中文翻译：

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反射冲击波后丙酮的自燃和热解

摘要 通过实验和数值研究了用氩气稀释的化学计量丙酮-氧气混合物的自燃。实验是在 1280 到 1810 K 的温度范围内以 [M]50 ≈ 10−5 mol/cm3 的总气体浓度在反射冲击波之后进行的。通过记录甲基自由基 (λ = 216.5 nm) 的吸收信号和电子激发的 OH* 自由基 (λ = 308 nm) 和 CO2* 分子 (λ = 370 nm) 的发射信号来监测该过程。在各种详细动力学机制的框架内进行了数值模拟，以重现我们自己和已发表的关于丙酮在反射冲击波后热解和自燃的实验数据，包括基态和电子激发的 OH 中丙酮和 CH3 的浓度分布* 和二氧化碳*，以及自燃延迟时间的温度依赖性。已经确定，各种详细的动力学机制以不同程度的准确度描述了丙酮在冲击波中热解的动力学特性。同时，他们所有人都预测了测量的点火延迟在两倍以内。敏感性分析表明，决定丙酮热解的反应对支链点火过程仅产生轻微影响，因此相关速率常数仅轻微影响点火延迟时间。他们都将测得的点火延迟预测为两倍。敏感性分析表明，决定丙酮热解的反应对支链点火过程仅产生轻微影响，因此相关速率常数仅轻微影响点火延迟时间。他们都将测得的点火延迟预测为两倍。敏感性分析表明，决定丙酮热解的反应对支链点火过程仅产生轻微影响，因此相关速率常数仅轻微影响点火延迟时间。