yc4s柴油机热力学仿真分析与试验车辆工程专业论文.docxVIP

YC4S柴油机热力学仿真分析与试验摘 YC4S柴油机热力学仿真分析与试验 摘 要 随着柴油机行、业的飞速发展，传统的研发流程由于缺少复杂而科学的理论计 算依据导致废品率高、试验成本高、研发周期长的弊端，已经无法满足现代柴油 机研制及市场更新换代的需求，利用现代CAE仿真技术在发动机图纸阶段对发动 机性能进行预测，通过优选方案减少发动机在试验阶段的方案数量显得尤为重要。 本文以玉柴新开发的YC4S柴油机作为研究对象，在发动机设计阶段对发动机的 动力性、经济性进行了预测。本文主要内容包括： (1)对国内外柴油机研发流程的现状和发展趋势进行了综合概述，同时还还 阐述了YC4S柴油机的研发背景。这些都为YC4S柴油机在研发过程中采用CAE 技术提供了必要依据。 (2)柴油机的动力性、经济性以及排放性是发动机最重要的特性，在图纸设 计阶段对它们的预测显得尤为重要。本文采用了Vibe燃烧放热模型和“Woschni 1978”放热模型对YC4S柴油机的动力性、经济性和排放性能进行预测。通过研 究表明：发动机采用18：1的压缩比，将原增压器基础上将涡轮增大70％，同时将 排气门开启角增大10degCRA、气门重叠角减小10degCRA，能获得较好的综合性 能，标定转速时平均要小压力提高了0．37bar，功率提高了4．3kW，最低比油耗降 低了39／(kW／h)。 (3)选取不问的增压器做台架试验，检验计算机仿真分析的准确性，从而确 认计算机仿真分析对柴油机研发过程具有准确的指导意义。试验表明，001增压 器压端：C246(56)55Trim，O．56A／R，涡端：T232 f50)74Trim，0．40A／R参数比较 合理，可以得到更好的动力性和经济性。 关键词：柴油机；燃烧放热模型；增压器 万方数据 工程硕士学位论文Abstract 工程硕士学位论文 Abstract With the rapid development of diesel engine industry，nowadays，the traditional development process is no longer able to meet the needs for modern diesel engine development as well as for the market upgrade due to the lack of complex and scientific theoretical calculation，high reject rate，high test cost and long development cycle．Therefore，it is particularly important to adopt the modern CAE simulation technology to predict the performance of the engine at the stage of engine drawing design and reduce the engine test schemes at the test stage through the optimization of the scheme．This article，with the YC4S diesel engine which has been developed by Yuchai as the research target，has predicated the power and cost effectiveness of the engine at the stage of the engine．The main points of this paper include： (1)It summarizes the present situation and development trend of the domestic and foreign diesel engines，and has expounded the background of developing the YC4S diesel，which has provided necessary basis for adopting the CAE technology during the research process of the YC4S diesel． (2)The power，cost effectiveness and emission of the diesel engine are the most important characteristics of the e