CAJ | 학술논문

汽油机部分负荷工况下,发动机的几何压缩比虽然不变,但由于进气量的减少而导致实际压缩比的下降,定量分析了这一工况下的损失构成。计算表明,由于实际压缩比的下降导致的损失较明显,因而必须重视发动机可变压缩比技术的应用研究。进一步提出了发动机可变压缩比技术方案应满足的基本要求并对现有的一些技术方案的特点进行了分析。
기유궤부분부하공황하,발동궤적궤하압축비수연불변,단유우진기량적감소이도치실제압축비적하강,정량분석료저일공황하적손실구성。계산표명,유우실제압축비적하강도치적손실교명현,인이필수중시발동궤가변압축비기술적응용연구。진일보제출료발동궤가변압축비기술방안응만족적기본요구병대현유적일사기술방안적특점진행료분석。
Spark-Ignited（SI） engines operate at relatively low loads with fixed geometric compression ratio,but effective compression ratio is reduced by decreasing intake gas mass-flow.The components of SI engine losses during part-load conditions are analyzed quantitatively in this paper.The calculation result shows that the losses due to effective compression ratio decreasing are prominent.So it is necessary to attach importance to variable compression ratio（VCR） technology.In addition,the design guideline for VCR engines is proposed and established.Several existing VCR concepts are evaluated according to these guidelines.