乙醇对汽油火焰碳烟生成特性影响的试验研究

Effect of Ethanol Addition in Gasoline on Soot Formation Characteristics in Diffusion Flames

设计并制作了一套新型的能够产生稳定层流火焰的液体燃烧器。将体积分数为0%、20%、50%和85%的无水乙醇混入92#汽油配制出了不同掺混比的乙醇汽油混合燃料,应用光学诊断技术在常压下对各燃料稳定火焰中的碳烟浓度分布进行测量,研究了添加乙醇对汽油火焰中碳烟生成特性的影响。研究结果表明:在保证碳元素流量为6.05g/h的情况下,随着燃料内乙醇的增加,各燃料均能生成稳定火焰,火焰高度保持在(50±1)mm;火焰中各个高度上的碳烟浓度都出现不同程度的降低;碳烟生成总量呈现直线下降规律,E20、E50、E85火焰中的碳烟总量相对于E0火焰分别降低了16.20%、37.77%和61.66%。

A novel liquid fuel combustion apparatus that can produce stable laminar diffusion flames was designed and set up. Gasoline-ethanol blends of 0%, 20%, 50% and 85% of ethanol in volume were used as fuel. Soot concentration profiles under atmospheric pressure were measured with an optical diagnostic technique to examine how adding ethanol to gasoline affects soot formation. The test results show that these gasoline-ethanol blends can generate stable diffusion flames with visible heights remaining at （50 ± 1） mm with increased amount of ethanol in gasoline under the condition of a fixed carbon flow rate of 6.05 g/h, that soot concentrations at different heights are reduced to different degrees, and that the total soot decreases almost linearly. The totals of soot in the flames fuelled by blends of 20%, 50%, and 85% ethanol are reduced by 16.20%, 37.77% and 61.66% respectively against that in the gasoline flame.