Experimental and computational investigations are carried out to elucidate the fundamental mechanisms of autoignition of surrogates of jet-fuels at elevated pressures up to 6 bar. The jet-fuels tested are JP-8, Jet-A, and JP-5, and the surrogates tested are the Aachen Surrogate made up of 80 % n-decane and 20 % 1,3,5-trimethylbenzene by mass, Surrogate C made up of 60 % n-dodecane, 20 % methylcyclohexane and 20 % o-xylene by volume, and the 2nd generation Princeton Surrogate made up of 40.4 % n-dodecane, 29.5 % 2,2,4-trimethylpentane, 7.3 % 1,3,5-trimethylbenzene and 22.8 % n-propylbenzene by mole. Using the counterflow configuration, an axisymmetric flow of a gaseous oxidizer stream, made up of a mixture of oxygen and nitrogen, is directed over the surface of an evaporating pool of a liquid fuel. The experiments are conducted at a fixed value of mass fraction of oxygen in the oxidizer stream and at a fixed value of the strain rate. The temperature of the oxidizer stream at autoignition, T_ig, is measured as a function of pressure, p. Experimental results show that the critical conditions, of autoignition of the surrogates are close to that of the jet-fuels. Overall the critical conditions of autoignition of Surrogate C agree best with those of the jet-fuels. Computations were performed using skeletal mechanisms constructed from a detailed mechanism. Predictions of the critical conditions of autoignition of the surrogates are found to agree well with measurements. Computations show that low-temperature chemistry plays a significant role in promoting autoignition for all surrogates. The low-temperature chemistry, of the component of the surrogate with the greatest volatility, was found to have the most influence on the critical conditions of autoignition.

进行了实验和计算研究，以阐明在高达6 bar的高压下，代用燃料替代物自动点火的基本机理。测试的喷气燃料是JP-8，Jet-A和JP-5，测试的替代物是质量分数为80％的正癸烷和20％的1,3,5-三甲基苯组成的亚琛代用品，代用品C由60％正十二烷，20％甲基环己烷和20％邻二甲苯组成，第二代Princeton Surrogate由40.4％正十二烷，29.5％2,2,4-三甲基戊烷，7.3％1组成， 3,5-三甲基苯和22.8％n-摩尔的丙基苯。使用逆流构造，由氧气和氮气的混合物组成的气态氧化剂流的轴对称流被引导到液体燃料的蒸发池的表面上方。实验是在氧化剂流中氧气的质量分数的固定值和应变率的固定值下进行的。自燃时氧化剂物流的温度T _ig是压力p的函数。实验结果表明，替代物自燃的临界条件与喷气燃料的接近。总体而言，替代C的自燃临界条件与喷气燃料的临界条件最吻合。使用由详细机制构建的骨骼机制进行计算。发现替代物自燃的关键条件的预测与测量结果非常吻合。计算表明，低温化学在促进所有替代物的自燃中起着重要作用。已发现具有最大挥发性的替代物组分的低温化学性质对自燃的临界条件影响最大。