高辛烷值组分对正庚烷着火燃烧特性的影响  

Effects of High-Octane Components on the Ignition Characteristics of N-Heptane

作　　者：汪映[1] 白元启 王鹏[1] 沈振兴[1] WANG Ying;BAI Yuanqi;WANG Peng;SHEN Zhenxing(School of Energy and Power Engineering,Xi＇an Jiaotong University,Xi＇an 710049,China)

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2018年第11期30-36,80,共8页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(91541118;51776162);中央高校基本科研业务费专项资金资助项目(XJJ2016051)

摘　　要：采用动力学模拟方法,研究了乙醇、异辛烷和甲苯这3种乙醇汽油中主要高辛烷值燃料组分的引入对正庚烷着火特性的动力学影响。研究结果表明:在初始温度高于1 000K左右的高温条件下,3种高辛烷值燃料组分的引入对燃料着火滞燃期几乎没有影响;在中低温条件下,高辛烷值组分的引入对燃料着火滞燃期影响显著。这是因为,低温条件下高辛烷值组分的引入对正庚烷氧化脱氢反应起到了抑制作用,进而影响了随后的低温链式反应,这种抑制作用使得正庚烷低温放热减弱、温度上升缓慢、着火向后延迟。在所研究的3种高辛烷值燃料中,乙醇抑制正庚烷着火的效果最显著,甲苯和异辛烷延迟正庚烷着火的效果相差不大,甲苯略微强于异辛烷。The kinetic effects of three different kinds of high-octane components in the ethanol gasoline such as ethanol, isooctane and toluene on the ignition characteristics of n heptane are studied with the method of kinetic simulation. Results show that when the initial temperature is more than 1 000 K, the introduction of three different kinds of high octane fuels has almost no influence on the ignition delay of n -heptane; whereas the high octane fuels has obvious influence on the ignition delay of n -heptane at low initial temperatures. This is due to the fact that the introduction of high octane fuel at low temperatures inhibits the oxidative dehydrogenation of n heptane, and hence influencing the subsequent low temperature chain reaction. In this way, the heat release of n heptane during the low temperature stage is reduced, and the temperature rises slowly, thus the ignition is delayed. Of the three kinds of high octane fuels studied in this paper, the ethanol shows the strongest effect on delaying the ignition of n heptane fuel. The effects of toluene and isooctane on the ignition delay of n- heptane are almost the same, and toluene shows slightly stronger delaying effect than isooctane.

关 键 词：着火滞燃期 高辛烷值燃料 正庚烷 

分 类 号：TK42[动力工程及工程热物理—动力机械及工程]