摘要
基于电控燃油喷射柴油机的全气缸取样系统,利用场发射透射电子显微镜和图像处理技术,对柴油机燃烧过程中微粒微观结构的变化进行了研究。结果表明,在燃烧过程中,层面间距、曲率的变化范围分别为0.36～0.40nm、1.22～1.33,且呈现在急燃期内减小,缓燃期内增加,此后逐渐减小的趋势;而微晶尺寸在1～2.2nm变化,呈现在急燃期内增加,缓燃期内减小,此后逐渐增加的趋势。此外,随着共轨压力的升高、燃空当量比的增加,层面间距、曲率减小而微晶尺寸增加;随着发动机转速的增加,层面间距、曲率增加而微晶尺寸减小。
Microstructure of the in-cylinder particulates obtained by a total cylinder sampling system were investigated by a field emission gun transmission electron microscopy （ FEG TEM ）, and microstructure characteristics like fringe separation distance, fringe length and tortuosity from the TEM image were extracted by the image processing algorithms. Experimental results shows that fringe separation distance is in the range of 0.36 to 0.40 nm and tortuosity is in the range of 1.22 to 1.33 during combustion, and these show a reducing trend in rapid combustion phase, increasing trend in mixing-controlled combustion phase, and reducing trend afterward. Fringe length is in the range of 1 to 2.2 nm, and it shows an increasing trend in rapid combustion phase, a reducing trend in mixing-controlled combustion phase, and an increasing trend afterward. Fringe separation distance and tortuosity are reduced while fringe length is increased with the increase of common rail pressure and fuel/air ratio. Fringe separation distance and tortuosity are increased while fringe length is reduced with the increase of engine speed.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2010年第3期221-227,共7页
Transactions of Csice
基金
国家重点基础研究发展计划资助项目(2002CB2603)
国家自然科学基金资助项目(50476067)
关键词
柴油机微粒
全气缸取样系统
微观结构
微晶尺寸
层面间距
曲率
Diesel particulate
Total cylinder sampling system
Microstructure
Fringe length
Fringe separation distance
Tortuosity
