煤油及其替代燃料点火延迟特性实验研究

Experimental Study on Ignition Delay of Kerosene and Surrogate Fuel

为研究煤油的点火特性,在反射型激波管中测量了煤油及替代燃料的点火延迟时间。通过测量激波压力信号和OH自由基光强信号,分析了点火温度、当量比对煤油点火延迟时间的影响。实验温度范围为1100~1800K,压力为0.1MPa,反应当量比为0.5,1.0,1.5。选用正癸烷（80%）和三甲基苯（20%）组成的替代燃料,在相同实验条件下比较了替代燃料对煤油点火模拟的准确性。结果表明随着点火温度升高和当量比的降低,煤油及其替代燃料的点火延迟时间缩短,点火延迟时间的对数与温度倒数成正比。选定的替代燃料可以较好地模拟实际煤油的点火延迟过程。

To investigate the ignition characteristics of kerosene,ignition delay time of kerosene and surrogate fuel were measured in a reflected shock tube.The effects of ignition temperature and equivalent ratio on ignition delay time were analyzed by monitoring both the pressure history and the emitted light of OH radicals. The temperature range was from 1100 K to 1800 K,the pressure were nearly 0.1MPa and equivalence ratios varied as0.5,1.0,1.5. A surrogate fuel model consisting of 80% n-decane and 20% trimethylbenzene in mole fraction respectively was selected to simulate kerosene in the same experimental conditions. The experiment results show that the ignition delay time of kerosene and surrogate fuel decreased with the increase of initial temperature and decrease of equivalent ratio. The logarithmic value of ignition delay time was proportional to the reciprocal of temperature. The surrogate fuel can well simulate the ingnition delay of kerosene.