生物柴油掺烧比对柴油机颗粒物排放影响的试验研究

Experimental Study on the Effect of Biodiesel Blend Percentage on Particulate Emission of a Direct Injection Diesel Engine

在四缸柴油机1800 r/min的5个工况下开展了针对颗粒物排放的研究,燃油采用超低硫柴油、生物柴油和二者的混合物。4种混合燃料中分别含有生物柴油的体积分数是19.6%,39.4%,59.4%和79.6%,对应的氧质量分数分别是2%,4%,6%和8%。研究结果显示,随着负荷的增加,烟度、颗粒物质量浓度、几何平均直径及颗粒物数量均增加;随着燃料中氧质量分数的增加,烟度和颗粒物质量浓度减小、几何平均直径变小,但颗粒物数量明显增加。

Experiments were conducted on a 4-cylinder direct-injection diesel engine using ultra low sulfur diesel,biodiesel and their blends,to investigate the particulate emissions of the engine under five engine loads at an engine speed of 1800 r/min.Blended fuels containing 19.6%,39.4%,59.4%and 79.6%by volume of biodiesel,corresponding to 2%,4%,6%and 8%by mass of oxygen in the blended fuel,were used.With the engine load increase,the smoke opacity,particulate mass concentration,geometry mean diameter and particle numbers are all increased.With an increase of biodiesel in the fuel the smoke opacity and particulate mass concentration are all reduced.Meanwhile,for submicron particles,the geometry mean diameter of the particles becomes smaller but the total number concentration increases obviously.