摘要
在加热激波管上首次测量了正壬烷/空气在宽温度范围的点火延迟时间。点火温度684-1448 K,点火压力2.0和15.0 atm,当量比0.5,1.0和2.0。结果显示,在800-950 K温度区间点火延迟出现负温度效应,即随温度的降低点火延迟时间几乎保持不变或者反而变短,如图1所示。本文实验数据与LLNL~[1]机理预测结果相符合。本文系统地研究了温度、压力和当量比对点火延迟时间的影响。敏感度分析显示影响正壬烷/空气点火延迟的关键反应在高低温条件下是不一样的,路径分析显示燃料消耗的反应路径在高低温条件下也是不一样的。
Ignition delay times of n-nonane/air were firstly measured behind reflected shock waves over a wide temperature range of 684-1448 K, pressures of 2.0 and 15.0 atm, and equivalence ratios of 0.5, 1.0, and 2.0. Results show that the negative-temperature-coefficient(NTC)behavior of the ignition delay was occurred at temperatures of 800-950 K, as displayed in Fig. 1. Current experimental data are in satisfactory agreement with predictions of LLNL mechanism. The effects of temperature, pressure, and equivalence ratio on the ignition delay have been discussed systematically. Sensitivity analysis indicates that key reactions affecting n-nonane/air ignition at high and low temperatures are quite different, and reaction pathway analysis reveals that consumption pathways of the fuel at high and low temperatures are also quite different.
引文
[1]Westbrook C K,Pitz W J,Herbinet O,Curran H J,Silke E J.Combust.Flame 2009,156,181.