在激波管中利用反射激波后高温环境加热燃料,以燃料点火过程中氢氧自由基特征发射光谱强度的急剧变化作为点火发生的标志,在温度范围800-1650K,压力0.2MPa,0.7MPa,1.2MPa,化学当量比为0.5,1,2,O2浓度为空气含量20%的条件下,进行了C2H4/O2/Ar混合气在低稀释度条件下点火特性的实验研究.获得了乙烯点火延时随温度、压力、化学当量比、燃料以及氧化剂浓度等参数变化的拟合关系式.对乙烯点火转爆轰现象进行了初步观察,考察了初始温度对乙烯点火特性以及点火转爆轰的影响.
Ignition delay characteristics of ethylene/O2/Ar mixtures have been studied behind reflected shock waves in a shock tube by monitoring the steepest rise of the characteristic emission of OH radical at 306.5 nm. Experiments were conducted with low argon dilution, covering a temperature range of 800-1 650 K, at pressures of 0.2, 0.7 and 1.2 MPa, and with equivalence ratios of 0.5, 1 and 2. The oxygen content of the test mixtures was about 20%. The correlation formula of ignition delay dependence on temperature, pressure, equivalence ratios and fuel and oxygen mole fraction was obtained. The transition of ethylene ignition to detonation was observed with different initial temperatures, and the influence of initial temperature on ignition delay characteristics of ethylene was also discussed.