G发动机开发和燃烧性能研究.pdf

满足国Ш G 发动机开发和燃烧性能的研究摘要随着汽车工业的发展,研发节能、环保和安全技术成为关键问题。本文根据我国和国外天然气发动机技术应用的经验,结合东风汽车公司承担的国家“十五”清洁汽车关键技术专题项目“电控 G 公交车的研究开发”课题, 提出了 EQD180N-G 发动机”研究开发方案,进行了工作过程的模拟计算和燃烧分析。开发出满足国 3 G 发动机。本文首先综述了天然气汽车发展的历史, 详细地研究了国内外天然气发动机的分类和技术特点。在分析国内外天然气发动机技术的基础上, 提出了满足国 3 G 发动机开发方案;以 EQD180-20 柴油机为基础机型,在基本不改变原机结构的前提下,对燃烧系统、进排气系统(包括进、排气道) 、气缸盖、活塞和增压中冷系统进行相应的变型设计; 采用稀薄燃烧、增压(空-空)中冷、低涡流燃烧系统、电控分组点火、开环控制、G 喷射系统和氧化型催化器等技术,降低排放,保持天然气发动机的动力性和经济性。本文对缸内燃烧进行了一维的数值模拟分析,研究压缩比、点火提前角和进气门正时的影响; G 发动机的工作过程进行三维数值计算,对缸内流动等内容进行系统研究;预测可靠性的薄弱环节,提出改进措施。 G 发动机电控系统匹配的基本策略。对天然气电控喷射系统进行试验优化匹配。进行氧化型催化转化器的性能试验。研制出点燃式电控喷射单燃料 EQD180N-G 发动机, 其性能和可靠性达到产品设计要求,排放满足国Ⅲ标准。本文探索和总结的东风天然气发动机开发流程、方法和经验, 可为今后代用燃料发动机的开发提供借鉴和参考。关键词: 天然气发动机燃烧电控排放 THE DEVELOPMENT OF MONO-FUEL ELECTRONIC G ENGINE MEETING EURO Ш REQIREMENT AND STUDY OF COMBUSTION PERFORMANCE ABSTRACT As auto industry development, it is important to study the economic saving, environmental protection and safety tec hnology. According to the government project of “The development of the M ono fuel engine with electrical control injection system” in china, and the appl ication experience of G in our country and abroad, the developing stra tegy G engine has been suggested and simulated calculation bustion analyses for working processes have pleted in this paper. The E QD180N-G engine with electrical control injection system has been developed . At first the history of CNG engine and vehicle was introduced which included the catalogs G engine and t echnical feature in detail. Based on the fundament of analyses of abroad and our G engine technology, the developing strategy G engine has suggested. Based on the EQD180-20 diesel which the basic construction unc hanged, the necessary modified designing G engine was made which included combustion system, intake and exhaust system, cylinder head, piston, and turbocharger. At the same time, the technonogy of lean burn, cooling turbocharger, low bustion system, separated united ignition control system ,