火花点火发动机爆震燃烧特性的研究  

A Study on the Characterization of Knock in a Spark Ignition Engine

作　　者：王良煜[1] 尚秀镜[1] 刘文胜[1] 李建权[1] 傅茂林[1] 

机构地区：[1]天津大学清华大学工程力学系

出　　处：《内燃机学报》1998年第2期176-183,共8页Transactions of Csice

基　　金：国家攀登计划资助项目

摘　　要：本文介绍了采用高速摄影法和同步记录气缸压力示功图，对火花点火发动机爆震燃烧特性进行的实验研究。实验结果表明，爆震起因于末端混合气的自燃。爆震时末端气体急剧放热而形成压力波，导致爆震所特有的压力振荡。压力波传播速度越快，振荡频率越高，爆震也越强。压力振荡的能量主要集中在少数几个频域内，且越集中于高频区域，爆震越强。同一循环燃烧室内不同空间位置的压力状况各不相同，同一工况的不同循环间爆震的特征参数也不相同，反映了爆震时压力波传播的复杂性。因而对爆震工况进行评价时，应该考虑多个循环的综合影响。The characterization of knock in a spark ignition engine was experimentally investigated using high speed photography together with the cylinder pressure measurement.The experimental results show that knock is resulted from end gas autoignition,and the pressure wave leading to pressure oscillation inherent in knock is formed due to sharp energy release.The greater the traveling speed of pressure wave,the higher frequency of the pressure oscillation,and the more severe the knock.The energy of pressure oscillating mainly focused on a few ranges of frequency.The higher frequency it focused on,the greater the knock intensity.The state of in cylinder pressure distribution is not identical spatially in chamber.The characteristic parameter of knock varies among cycles under the same condition.It indicated the complexity of knocking combustion,and the effect of different cycles should be taken into account comprehensively when knocking combustion is evaluated.

关 键 词：自燃 爆震 压力振荡 循环变动 汽油机 火花点火 

分 类 号：TK411.22[动力工程及工程热物理—动力机械及工程]