基于全可变气门机构的无节气门汽油机进气性能

Intake performance of unthrottled gasoline engines based on fully variable valve systems

全可变气门机构(FVVS)对汽车的节能减排具有重要意义。该文采用位移传感器试验测量了全可变气门机构的气门升程,采用进气流量计试验测量了无节气门汽油机的进气量。根据实测气门升程和充量系数,分析了全可变气门机构的气门运动特性,讨论了全可变气门机构对进气量的调节作用。研究结果表明:全可变气门机构可实现气门最大升程和气门开启持续角在较大范围内的连续可变,完全能够采用进气门早关或进气门晚关的方式实现对进气量的调节。

For unthrottled gasoline engines, substitution of fully variable valve systems （FVVSs） for throttles is very important for energy saving and emission reduction. A displacement sensor was used to measure the valve lift and intake efficiency of FVVS with an intake flow-meter used to measure the air inflow of the unthrottled gasoline engines. The movement characteristics of the intake valve were analyzed according to the test results, with the adjustments of the intake air volume by FVVS being discussed. The results show that the fully variable valve system enables the maximum valve lift and opening duration to continuously vary in a large range, so the intake air inflow can be controlled though timing and early intake valve closing or late intake valve closing.