车用汽油机整机性能评价系统的开发设计.doc

车用汽油机整机性能评价系统的开发设计 摘要 车用汽油机性能主要包括动力性、经济性、排放噪声及其可靠耐久性等方面。衡量质量实质上就是对整性能进行综合评定。 本课题采用汽油机的最大功率、最大扭矩、有效燃油消耗率、排放标准、比功率、升功率六个参数作为评价指标，采用层次分析法对各个指标的重要性进行分析，确定其所对应的权重，采用数学统计法和模糊综合评判法，为定量指标建立其相应的隶属函数，为定性指标划分其相应的适宜度等级，再用模糊数学理论计算出反映汽油机产品整机性能Visual Basic编写一个基于该评价方案的车用汽油机整体性能评价系统。 关键词：车用汽油机；性能指标；评价体系；层次分析法；模糊综合评价方法 THE DESIGN OF AUTOMOTIVE GASOLINE ENGINE PERFORMANCE EVALUATION SYSTEM ABSTRACT Automotive gasoline engine performance mainly includes power performance, fuel economy performance, emissions performance, reliable performance and noise. Automotive gasoline engine quality is essentially measured by its comprehensive performance. This project has designed a evaluation system on Visual Basic development platform and chose 4 automotive gasoline engines for instance. Considering the data acquisition and practicability, this project choose maximum power, maximum torque, specific mass , Liters power ,effective specific fuel consumption and emissions standards which are easy to get to value the engine performance. It adopts the analytic hierarchy process to analyze the importance of every index, and use the mathematical statistics method and fuzzy comprehensive evaluation method to establish the corresponding membership functions for the quantitative indicators and the level for its suitability qualitative indicators, It calculates the performance score that reflects the gasoline engine products with fuzzy mathematical theory. This project writes a program of automobile gasoline engine overall performance evaluation system based on that evaluation methods. Key words: automotive gasoline engine; performance index; evaluation system; Analytic hierarchy process; The fuzzy comprehensive evaluation method 目 录 1 绪论 1 1.1 课题背景及目的 1 1.2 国内外设计状况 1 1.3 设计采用的途径 2 2 发动机的性能指标 4 2.1 动力性指标 4 2.2 经济性指标 5 2.3 强化指标 5 2.4 紧凑性指标 6 2.5 其它指标 6 2.6 本课题选用的评价指标 6 3 车用汽油机性能提升技术 8 3.1 增压发动机 8 3.1.1 涡轮增压 8 3.1.2 机械增压 8 3.2 电控燃油喷射系统（EFI） 8 3.3 缸内直喷汽油发动机 9 3.4 EGR技术 11 3.5