摘要
利用ELPI(电子低压冲击器)对不同转速、不同负荷以及安装DOC(氧化催化转化器)前后颗粒物排放及粒径分布进行了研究.结果表明:无论安装DOC与否,柴油机排放颗粒物数浓度均随发动机转速的增加而增加.增大负荷,颗粒物数浓度峰值处的粒径也随之增大.经过DOC催化转化后,柴油机排放颗粒物的大部分仍呈单峰正态分布,且DOC对核模态粒子的氧化转化效率较高.经过DOC后,在低转速下,不同粒径的颗粒物数浓度均有所降低;中、高转速下,DOC对粒径大于120 nm的颗粒物数浓度无明显降低作用.
Measurements of particle number emissions and particle size distributions from a diesel engine under different rotation speeds and loads,and with and without a diesel oxidation catalyst（DOC）,were performed using an electrical low-pressure impactor（ELPI）.The results showed that the number concentration of particles increased with the speed of the engine regardless of whether or not the DOC was used.With increasing engine load,the peak number concentration occurred at a larger diameter.After the DOC,the particles still mostly showed a unimodal normal distribution,and the DOC had a high conversion efficiency on nucleation mode particles.Under low engine speed conditions,particles at all diameters on average showed lower number concentrations.Under medium and high engine speed conditions,the DOC showed no clear impact on number concentrations of particles greater than 120 nm in diameter.
出处
《环境科学研究》
EI
CAS
CSCD
北大核心
2011年第7期711-715,共5页
Research of Environmental Sciences
基金
国家自然科学基金项目(40805053)
关键词
柴油机
氧化催化转化器(DOC)
颗粒物
数浓度
粒径分布
diesel engine
diesel oxidation catalyst（DOC）
particulate matter
number concentration
size distribution
