该文选取丙醇、癸烷、柴油为实验液滴燃料,通过利用高速摄像机对液滴燃烧时火焰和粒径的实时测量,以及激光诱导白炽光(LII)对碳烟体积分数的测量方法,研究了重力场作用下液滴在垂直电场中的燃烧特性。研究结果表明: 三种燃料火焰高度均随极板间电压的增加而增加,火焰宽度随极板间电压的增加而减小; 丙醇燃烧基本不生成碳烟,癸烷及柴油火焰中碳烟体积分数随极板间电压增加而减少; 燃烧速率常数随极板间电压的增加而增加,其中丙醇、癸烷、柴油燃烧速率常数最大增加值分别为9%、20%、30%。分析研究表明: 电场对火焰的拉伸有助于抑制碳烟的生成和促进碳烟的氧化,降低了火焰中的碳烟生成量,削弱了碳烟对外的辐射换热,从而促进了燃料的燃烧。

Propanol, n-decane, and diesel droplets were selected as experimental samples to study combustion behavior of fuel droplets in a vertical electric field under gravity. A high speed camera was used to measure the combustion flame and droplet size, with laser-induced incandescence (LII) applied to determining soot volume fractions. The results show that the flame height of each fuel increases with increasing electrodes voltage, while the flame width decreases with increasing electrodes voltage. Propanol droplet combustion does not produce soot, with n-decane and diesel flame soot volume fraction decreasing with increasing electrodes voltage. Burning rate constants increase with increasing electrodes voltage with the maximum burning rate constant increasing by 9%, 20%, and 30% for propanol, decane, and diesel, respectively. Analyses show that electric field stretching on the flame induces soot formation suppression and promotes soot oxidation, reducing soot generation and weakening soot external radiation heat transfer, so as to promote fuel combustion.