正庚烷掺烧甲醇时炭烟和PAHs生成的数值模拟

摘要

利用Chemkin Pro软件中的均质压燃模型,采用正庚烷详细化学动力学机理和炭烟生成氧化机理,模拟了甲醇对正庚烷燃烧时炭烟生成的影响.模拟结果表明:随着甲醇含量的增加,炭烟生成量减少,炭烟颗粒直径变小；掺入少量甲醇时,炭烟颗粒平均直径明显变小；当含甲醇量达到15％时,平均颗粒直径稍有变小；正庚烷中加入甲醇后,燃料中含氧量增加,有更多的炭烟气态前驱物和PAH被氧化,从而抑制了炭烟的生成.%With the HCCI model of Chemkin-Pro software, the influence of methanol on soot formation in n-heptane combustion was simulated based on the n-heptane detailed chemical kinetic mechanism and soot oxidation mechanism. The results show that, with the increase of methanol content, the soot reduces and its diameter decreases. Mixing with a little methanol, the soot mean diameter obviously decreases. The methanol content reaches 15% , the soot mean diameter slightly decreases. Mixing with methanol, the oxygen content of n-heptane fuel increases, more soot gaseous precursors and PAH are oxidized and thereby the soot is suppressed.