火花点火式发动机燃烧过程中缸内气流运动研究

通常在发动机倒拖工况下测量和研究缸内气流运动，对于燃烧过程中缸内流动规律的测量和研究还很少。在一台单缸四气门火花点火式发动机上，用激光多普勒测速仪分别在发动机着火和倒拖条件下测量和分析了燃烧室气流运动的规律。研究结果表明，在燃烧和排气阶段，缸内气流的平均速度与倒拖时有较大差别，而且燃烧速度越快，燃烧过程中气流运动速度的变化越剧烈。

Study on In-Cylinder Flow During Combustion in a Spark Ignition Engine

The measurement and study of the air flow in the cylinder is usually made under motored conditions.Only in very few cases,this study was carried out under firing conditions.In this paper the in cylinder air motion and its interaction with combustion are studied under both motored and firing conditions by LDA in a single cylinder 4 valve S.I.engine.The results show that during intake,compression,expansion and exhaust processes,mean velocities of air flow in the cylinder under firing condition are quite different from those under motored conditions.Furthermore,the higher is the combustion velocity,the greater is the variation of the mean velocity of air flow.