可变几何排气管增压系统的设计与试验研究

摘要

针对某车用6缸机高低转速工况兼顾的问题提出了一种可变几何排气管增压系统,并进行了稳态模拟试验,分别用原机脉冲增压系统排气管和新加工的准定压增压系统排气管来模拟可变几何排气管增压系统的可控阀门关和开的状态.试验结果表明:在低速工况关闭可控阀门,可以充分利用脉冲能量;在高速工况打开可控阀门,可以减小泵气损失.%A variable geometry exhaust manifold (VGEM) system was proposed and its related steady simulation experiments were carried out in order to improve a 6-cylinder vehicle engine performance at both high and low speed. The opening and closing state of controllable valve for VGEM were simulated by the original pulse turbocharging and newly-machined quasi-constant pressure turbocharging exhaust manifold respectively. The results show that closing the controllable valve at low speed can make full use of pulse energy; while opening the controllable valve at high speed can reduce pumping loss.