Characteristics of ultrafine particles emitted from a dimethyl ether (DME) engine

作     者：LI XinLing HUANG Zhen WANG JiaSong WU JunHua 

作者机构：Center for Combustion and Environmental Technology Shanghai Jiao Tong University Shanghai 200240 China School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China 

出 版 物：《Chinese Science Bulletin》 (中国科学通报)

年 卷 期：2008年第53卷第2期

页      面：304-312页

核心收录：

学科分类：080703[工学-动力机械及工程] 08[工学] 0807[工学-动力工程及工程热物理] 

基　　金：the National Key Technologies Research and Development Program of China (Grant No. 2003BA408B12A) 

主　　题：二甲基醚 柴油机 发动机 微粒 

摘      要：Measurements of exhaust particle number concentration and size distribution from a dimethyl ether (DME) engine at different engine loads and speeds were carried out by using a two-stage dilution sys- tem and an SMPS. The results of the DME engine were compared with those of the original diesel en- gine. The fuel composition had significant effects on the exhaust particle size distribution, the total exhaust particle number and mass concentrations. Compared with those of the DME engine, the parti- cle mass emissions of the diesel engine increased 5.7-17.7 times. At high engine speed (n=2200 r/min), compared with those of the DME engine, the total particle number emissions of the diesel engine in- creased 0.75-2.2 times, while the total particle number emissions of the diesel engine decreased by about 50%-80% for middle and high loads at middle engine speed (n=1400 r/min). Compared with those of the DME engine, the total exhaust particle number concentrations in the accumulation mode of the diesel engine increased 4.2-62.6 times and the exhaust particle geometric number mean diameters in the accumulation mode increased by about 10-30 nm. This correlated with higher oxygen level and lack of C-C bonds in DME. A lot of nucleation mode particles were emitted from the DME engine, this correlated with the processes of nucleation and condensation of the volatile and semi-volatile com- pounds in the exhaust gas.