【摘要】 为了解正丁醇—柴油燃烧碳烟前驱物（PAHs）的形成过程,以正庚烷—正丁醇—多环芳香烃—甲苯简化机理作为正丁醇—柴油混合燃料燃烧化学反应动力学机理,应用化学动力学软件建立零维发动机模型,模拟混合燃料在不同的进气温度（303 K、363 K、423 K）和当量比（0.5、1.0、1.5）条件下发动机内正丁醇—柴油燃烧PAHs的生成规律,并与纯柴油进行比较,进一步分析加入正丁醇后碳烟前驱物减少的原因。结果表明:在不同的进气温度和当量比下,柴油中掺入20%的正丁醇（B20）时,在燃烧中期（CA50）碳烟前驱物苯（A₁）、萘（A₂）、菲（A₃）和芘（A₄）的生成均与C₂H₂、C₂H₃、C₃H₃、C₄H₃、C₄H₄和C₄H₅等燃烧中间小分子物质有关;B20与纯柴油（D100）相比,C₂H₂、C₂H₃、C₃H₃、C₄H₃、C₄H₄和C₄H₅等中间小分子物质的生成速率减慢且消耗速率较快,其负归一化反应系数要比D100条件下高0.2左右;同时,A₁、A₂、A₃和A₄的缸内生成速率和生成量也有所降低。因此,在柴油中掺入一定比例的正丁醇可以改善发动机PAHs和碳烟排放。更多还原

【Abstract】 To understand the formation process of soot precursors（ PAHs） with the n-butanol-diesel blend fuel combustion,the combustion model of engine was built by using chemistry dynamics software,and the n-heptane-n-butanol-PAH-toluene reduced mechanism was used as n-butanoldiesel blend fuel combustion chemical reaction kinetics to simulate the mixed fuel in different inlet temperature（ 303 K,363 K,423 K） and equivalent ratio（ 0. 5,1. 0,1. 5） under the condition of n-butanol-diesel blend fuel in the engine combustion of PAHs formation regularity,and comparing with pure diesel（ D100）,further analysis after joining n-butanol to reduce carbon smoke. Resultsshow that under different inlet temperature and equivalent ratio,the diesel blended with 20% of n-butanol（ B20）, benzene（ A₁）,naphthalene（ A₂）,philippines（ A₃） and pyrene（ A₄）generation were related with C₂H₂,C₂H₃,C₃H₃,C₄H₃,C₄H₄ and C₄H₅middle small molecules under burning mid（ CA50）; The B20 compared with the D100,C₂H₂,C₂H₃,C₃H₃,C₄H₃,C₄H₄ and C₄H₅middle small molecules generated slow rate and consumption rate faster,the normalization of negative reaction coefficient is higher than the D100 conditions around 0. 2; at the same time,A₁,A₂,A₃ and A₄formation rate and generation in cylinder are also reduced. Therefore,in the diesel blended with a percentage of n-butanol could improve engine PAHs and soot emission.更多还原