柴油/甲醇组合燃烧发动机的微粒排放及催化转化特性

Emissions and Oxidation Characteristics of Particulate from a Diesel/Methanol Compound Combustion Engine

在一台改造的自然吸气高速柴油机稳态工况下,试验分析了柴油/甲醇组合燃烧模式对发动机的燃烧特性、烟度、微粒(PM)质量排放、微粒中可溶性有机物(SOF)、微粒的数量浓度和尺寸分布的影响。同时,对微粒的氧化行为进行了观察。结果表明,柴油甲醇组合燃烧使得发动机烟度、微粒质量和数量排放大幅降低但是增加微粒中SOF的比例。经过催化转化后,烟度、微粒的质量排放和数量排放量进一步降低,微粒中SOF的比例亦降低,微粒的几何平均直径(GMD)略有所增加。

Experiments were conducted on a naturally aspirated modified diesel engine to investigate the effect of diesel/methanol compound combustion on combustion characteristics,smoke opacity,particulate mass emission,soluble organic fraction（SOF）in the particulate as well as particulate number emission and size distribution.Oxidation behavior of particulate was also investigated.Results show that diesel/methanol compound combustion decreases the smoke opacity,particulate mass emission and number emission but increases SOF in the particulate.After catalytic oxidation,smoke opacity,particulate mass emission and number emission and SOF in the particulate further decrease while the geometric mean diameter（GMD）of particulate slightly increases.