柴油机燃用甲醇-调合生物柴油的排放及颗粒形貌

Emission and particulate topography characteristics of diesel engine fuelled with methanol-blending biodiesel

在186FA发动机上,进行了燃用调合生物柴油和甲醇-调合生物柴油微乳化燃料的性能试验,采集了排气颗粒,分析了调合生物柴油掺烧甲醇对发动机性能的影响及燃烧颗粒的状态特征.结果表明:随着甲醇掺混比例的增加,发动机燃用甲醇-调合生物柴油微乳化燃料的燃油消耗率呈上升趋势,在低负荷时最为明显,中高负荷时差距较小;柴油机的HC排放升高,但随着负荷的增加逐渐降低,与调合生物柴油相比,掺烧甲醇可以同时有效减少NOx及碳烟排放,并且在高负荷工况下能够明显降低CO排放;颗粒微观结构表现出链状、枝状及团状等形态;随着甲醇比例的增加,颗粒的粒径分布逐渐向小粒径方向移动,团聚程度逐渐提高,结构排列更为紧密.

On the 186FA diesel engine , the experiments of blending biodiesel and methanol-blendingbiodiesel were carried out , and the exhaust particulates were collected. The effects of methanol-blendingbiodiesel on engine performance and topographic characteristics of particulates were also analyzed. results show that with the increasing of methanol proportion , the engine comsumption with micro-emulsionfuels is increased especially at low load with small difference for medium and high load , and the HC emission of diesel engine increases gradually. As the increasing load becomes big , the HC decreases slowly. Compared with blending biodiesel , the fuels mixed with methanol can effectively decrease NO, and PM emission , and at high load , CO emission is reduced evidently. The particulates for different fuels represent catenulate , dendritic and cluster structures. When the methanol proportion is increased , theparticulates become more compacted , and the size distribution of particulates is decreased with increasedaggregation degree.