天然气缸内直喷发动机在不同喷射和点火时刻下的排放与燃烧特性  

Particulate Emission and Combustion Characteristics of a Direct-Injection Natural Gas Engine under Various Injection and Ignition Timings

作　　者：刘亦夫[1] 刘兵[1] 刘亮[1] 曾科[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2011年第5期12-16,共5页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(50636040)

摘　　要：在一台缸内直喷火花点火天然气发动机上对不同喷射时刻和点火时刻下的微粒排放进行了试验研究,并对相关的燃烧和排放特性进行了分析.研究结果表明:随着喷油时刻和点火时刻的提前,发动机微粒排放增多;峰值粒径出现在29 nm附近,数量浓度达到1×107cm-3,而微粒的粒径分布没有发生太大变化;火焰发展期随着喷油时刻的提前而缩短,快速燃烧期在190°时达到最小值;随着点火时刻的提前,火焰发展期变长,快速燃烧期先减小后增大;NOx和HC排放均随喷油时刻和点火时刻的提前而增大.The particulate emission under various injection timings and ignition timings was experimentally investigated on a natural gas direct-injection spark-ignition engine,and the corresponding combustion and emission characteristics were also analyzed.The results show that the particulate emission increases with the advance of fuel injection timing and ignition timing,the peak of particle number concentration appears around the particle diameter of 29 nm with the value of 1×107 cm-3,but the size distribution varies slightly.The flame development duration decreases with the fuel injection timing advancing,and the rapid flame duration reaches the minimum value at the fuel injection timing of 190°.With the ignition timing advancing,the flame development duration increases.The rapid combustion duration firstly decreases with the advancing ignition timing,and then increases.Both NOx and HC concentrations increase with the advanced fuel injection timing and ignition timing.

关 键 词：缸内直喷 微粒排放 燃烧特性 

分 类 号：TK431.2[动力工程及工程热物理—动力机械及工程]