内燃机的换气过程是进、排气门开启,新鲜充量流入,废气流出,进、排气门关闭的过程。本文主要论述了四冲程内燃机的换气过程,并对换气过程中的损失做了分析。同时也对换气过程的一个重要参数——充量系数做了讨论,给出了提高充量系数的措施。最后对二冲程内燃机进行论述,并将之与四冲程内燃机进行了比较。 Internal combustion engine ventilation process is into, exhaust valve open, fresh charge inflow, exhaust outflow, into, exhaust valve closed process. This paper discusses the four-stroke internal combustion engine ventilation process, and the loss of the ventilation process is analyzed. At the same time, a discussion is made on the coefficient of charge, which is an important parameter of the ventilation process, and some measures to improve the coefficient of charge are given. Finally, two-stroke internal combustion engine is discussed and compared with four-stroke internal combustion engine.