Abstract The autoignition process of propane has been studied using an optically accessible rapid compression machine (RCM). The ignition delay times of the fuel were measured at two compressed pressures of approximately 21 and 30 bar, equivalence ratios of 0.5, 0.8, 1.0 and 1.2, and at various compressed gas temperatures. A detailed kinetic model was also used to simulate the autoignition. A new methodology was also developed and discussed to include the effect of heat transfer in the mechanism model simulation. The combustion process imaging was acquired using high-speed camera and the deflagration like combustion with blue continuum spectrum was observed close to the end of ignition delay at all of the studied conditions, excluding the condition with very long ignition delay (e.g., 90 ms). The deflagration concluded with detonation for most of the studied conditions. The excited radicals’ chemiluminescence emissions were acquired using flame spectrometer and Electron-Multiplying Charge-Coupled Device (EMCCD) with wavelength ranging from 280 nm to 700 nm. Several excited radicals were detected during autoignition process and their time-resolved intensity as a function of mixture conditions (pressure, temperature and equivalence ratio) were studied.

中文翻译：

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快速压缩机中丙烷混合物的自燃和火焰光谱

摘要 丙烷的自燃过程已使用光学可接近的快速压缩机 (RCM) 进行了研究。燃料的点火延迟时间是在大约 21 和 30 巴的两个压缩压力、0.5、0.8、1.0 和 1.2 的当量比以及各种压缩气体温度下测量的。详细的动力学模型也用于模拟自燃。还开发并讨论了一种新方法，以将热传递的影响包括在机制模型模拟中。使用高速相机获取燃烧过程成像，在所有研究条件下，除了点火延迟很长（例如，90 ms）的条件外，在接近点火延迟结束时观察到类似燃烧的蓝色连续谱. 在大多数研究条件下，爆燃以爆炸结束。使用火焰光谱仪和电子倍增电荷耦合器件 (EMCCD) 获得激发自由基的化学发光发射，波长范围为 280 nm 至 700 nm。在自燃过程中检测到几种激发态自由基，并研究了它们的时间分辨强度与混合条件（压力、温度和当量比）的关系。