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本文摘自伯尔法斯特大学机械制造学院的报告。二冲程和四冲程发动机采用废气渦轮增压时,比较两种方法的能量利用率,是以增压压力为基础的。用特性曲线的方法进行周密的比较,不仅计算困难,而且对短管路系统也不太准确,所以,对脉冲法采用众所周知的进、排气过程。文中指出,脉冲法较定压法优越的特点随增压压力的提高而迅速下降。就渦轮与压气机之间能量平衡的情况而言,不管取哪种方法,二冲程发动机均劣于四冲程发动机。另外又指出,二冲程发动机的扫气过程对于脉冲法的能量利用率具有显著的影响,而对定压法没有影响。
This article is taken from the report of the University of Belfast Mechanical Engineering. When two-stroke and four-stroke engines use exhaust turbocharging, the energy efficiency of the two methods is compared based on the boost pressure. The careful comparison with the method of characteristic curves not only computes the difficulty but also the accuracy of the short-circuit system. Therefore, the well-known pulse-in / out process is used for the pulse method. It is pointed out in the paper that the superiority of pulse method compared with constant pressure method decreases rapidly with the increase of supercharging pressure. Either way, the two-stroke engine is inferior to the four-stroke engine in terms of energy balance between the turbine and the compressor. In addition, it is pointed out that the scavenging process of a two-stroke engine has a significant effect on the energy utilization rate of the pulse method, but has no effect on the constant pressure method.