发动机进气门晚关对于进气过程的影响研究

Research on the Infl uence of Engine Intake Valve Late Closing on Intake Process

进气门晚关系统可以活塞上行的压缩过程中仍然保持进气门开启,使一部分气体排出缸外,从而降低进气量和降低有效压缩比。研究了不同的进气门晚关角度对于进气量的影响规律,研究结果表明进气门关闭越迟,活塞上行过程中排出的气量越多,相同进气压力下的进气量越少。同时,在相同的进气门晚关角度条件下,不同的气门型线,对于进气量的影响也有差异,气门晚关过程中的气门升程越高,活塞上行过程中排出的气量也越多。

The late intake valve closing system can keep the intake valve open during the compression process when the piston moves upward,so that a part of the gas is discharged out of the cylinder,thereby reducing the intake air volume and the eff ective compression ratio.The infl uence of diff erent intake valve late closing angles on the intake air volume is studied.The research results show that the later the intake valve closes,the more air volume is discharged during the upward movement of the piston,and the less air intake volume is at the same intake pressure.At the same time,under the same condition of the late closing angle of the intake valve,diff erent valve profi les have diff erent eff ects on the intake air volume.The higher the valve lift during the late valve closing process,the greater the amount of air discharged during the upward piston movement.many.