LPG与汽油燃料微粒排放的时效特性研究

介绍了应用液化石油气(LPG)和汽油燃料时，微粒排放时效特性的对比研究。试验在一台四冲程、水冷125mL、点燃式单缸电喷发动机上进行。试验结果表明：对于两种燃料，随着沉降时间的增加，微粒排放的粒数不但大幅度下降，其粒度分布规律也发生了明显的变化；LPG和汽油燃料排出的小粒径部分微粒在空气中存在时间短，在排出后15min左右即可大部分挥发或凝聚形成大粒径粒子，而挥发消失的颗粒物比率LPG大于汽油；80％以上的大粒径部分(≥O．237um)粒子是在沉降过程中形成的；在测试条件下，汽油燃料微粒排放的大粒径部分粒子比LPG燃料容易沉降或挥发，随着沉降时间的延长，LPG与汽油微粒排放物的粒度分布特性趋于同一水平。

Study of the Timing on Characteristics of Particulate Emissions for LPG and Gasoline Fuels

This paper presented the experimental studies of the timing characteristics on particulate in a SI engine fueled with LPG and gasoline fuel respectively.Experiments were carried out in a single cylinder,four-stroke,water-cooled,125 mL engine with electronic fuel injection.Test results showed that: for the two fuels,both the numbers of particulate and the size distributions were changed remarkably with the time elapsing.Most of the smaller particulates disappeared in 15 minutes due to the volatilization or the agglomeration.The ratio of volatilized particulates for LPG was larger than that of gasoline.Over 80% large particulates were agglomerated during the sedimentating process and the large particulates for gasoline was easier to sedimentate or volatilize than that of LPG under the testing conditions.The particulate characteristics of LPG and gasoline gave the same level of size distribution tendency after enough sedimentited time.