Understanding of ignition processes is central to design for reliable and safe aerospace combustor systems. Ignition is influenced by many factors including combustor geometry, flow conditions, fuel composition, turbulence intensity, ignition source, and energy deposition method. A toroidal jet-stirred reactor (TJSR) utilizes bulk fluid motion, presence of recirculation zones, a bulk residence time, and turbulence intensities which emulate characteristics relevant to cavity stabilized and swirl stabilized combustors. In this work, a TJSR was used to quantify ignitability and time-to-ignition of premixed ethylene and air. The effects of inlet temperature, residence time, and reactivity were studied on forced ignition processes. Experimental conditions ranged from residence times of 15–35 ms, mixture temperatures of 340–450 K, and equivalence ratios of 0.5–1 using capacitive spark-discharge ignition. The minimum equivalence ratio for ignition (MER), or the equivalence ratio at 50% probability, shows an inverse relationship with mixture temperature and residence time. Prior theory of real engine combustor performance for lean light off, proposed by Ballal and Lefebvre, was compared to the MER and displayed similar trends to the model. Spatially integrated OH* chemiluminescence was used to measure time to ignition within the reactor. Reduction in ignitibility was experienced as the time-to-ignition approached the residence time stressing the importance of device flow time scales in relation to kernel growth dynamics and ignition probability.

了解点火过程是设计可靠，安全的航空航天燃烧器系统的关键。点火受许多因素影响，包括燃烧室的几何形状，流动条件，燃料成分，湍流强度，点火源和能量沉积方法。环形射流搅拌反应器（TJSR）利用了整体流体运动，再循环区的存在，整体停留时间和湍流强度，它们模拟了与腔稳定和涡旋稳定的燃烧器有关的特性。在这项工作中，TJSR用于量化预混乙烯和空气的可燃性和点燃时间。研究了入口温度，停留时间和反应性对强制点火过程的影响。实验条件的范围为停留时间15–35 ms，混合物温度340–450 K，电容火花放电点火的当量比为0.5-1。最小点火当量比（MER）或50％概率下的当量比与混合物温度和停留时间呈反比关系。Ballal和Lefebvre提出的关于稀薄点火的实际发动机燃烧器性能的先验理论与MER进行了比较，并显示出与模型相似的趋势。使用空间积分的OH *化学发光来测量反应器内的着火时间。随着着火时间接近停留时间，着火性降低了，这着重强调了设备流动时间尺度相对于籽粒生长动力学和着火概率的重要性。或当量比为50％的概率时，与混合物温度和停留时间呈反比关系。Ballal和Lefebvre提出的用于稀薄点火的实际发动机燃烧器性能的先验理论与MER进行了比较，并显示出与模型相似的趋势。使用空间积分的OH *化学发光来测量反应器内的着火时间。随着着火时间接近停留时间，着火性降低了，这着重强调了设备流动时间尺度相对于籽粒生长动力学和着火概率的重要性。或当量比为50％的概率时，与混合物温度和停留时间呈反比关系。Ballal和Lefebvre提出的用于稀薄点火的实际发动机燃烧器性能的先验理论与MER进行了比较，并显示出与模型相似的趋势。使用空间积分的OH *化学发光来测量反应器内的着火时间。随着着火时间接近停留时间，着火性降低了，这着重强调了设备流动时间尺度相对于籽粒生长动力学和着火概率的重要性。使用空间积分的OH *化学发光来测量反应器内的着火时间。随着着火时间接近停留时间，着火性降低了，这着重强调了设备流动时间尺度相对于籽粒生长动力学和着火概率的重要性。使用空间积分的OH *化学发光来测量反应器内的着火时间。随着着火时间接近停留时间，着火性降低了，这着重强调了设备流动时间尺度相对于籽粒生长动力学和着火概率的重要性。