The effects on engine volumetric efficiency profile of various intake system components are analyzed in this paper, based on the understanding of the relationship between pressure wave actions and the general volumetric efficiency profile presented in a previous paper[1]. The effects result from either the change of the natural pressure wave period (length effect) or the amplitude of pressure waves (diameter effect). It was found that the general volumetric efficiency profile in the low to mid speed range is dominated by the total intake system length, while in the high speed range it is governed by primary pipe dimensions alone. The change of the total intake system length, in any part of the system from port to the air entry, shifts the volumetric efficiency profile along the engine speed axis, while the change of diameter has the influence only in a narrower range. The type of plenum, plenum spacing and the diameter profile of upstream components areonly minor factors. Based on those the design guidelines are presented.%本文建立在作者的前一篇文章[1]中对进气系统压力波动与发动机充气效率的关系研究的基础上,系统分析了进气系统各部件的设计参数对充气效率的影响.从压力波动机理上看,这些影响或源于压力波谐振周期(管长参数),或源于压力波幅值(管径参数).试验结果表明:在中、低速区域,充气效率曲线形态取决于进气系统的总长度,各部件之间的管长分布影响较小;而在高速区域则只与进气岐管参数有关.因而,任一部件长度参数的变化,如果改变了系统总长度,将导致充气效率曲线在转速轴上的平移,而管径参数则只在一相对狭窄的区域内对充气效率施以影响.在同一系统总长度前提下,进气歧管的交汇方式,在交汇处的间距,上游部件的形状等等,对发动机充气效率的影响甚微.基于上述结论,本文对进气系统的参数设计提出了几点指南.
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