摘要本文在零文假设的前提条件下建立了四冲程缸外喷射预混合火花点火汽油机热力学模型的快速计算程序。从质量守恒方程,能量守恒方程和热力学定律推导方程式,并根据汽缸工作过程中的不同特点进行求解。利用MATLAB程序进行发动机的仿真研究,得到了汽缸内主要参数在整个循环中的变化情况。重点研究了进气压力、点火时刻及压缩比等参数对发动机P-V图及指示热效率的影响,得到了不同点火时刻、压缩比和进气压力的P-V图和指示热效率。仿真结果与实际工作过程吻合情况良好。它可以为发动机的设计和改进工作提供理论计算依据,为开发新型发动机和旧发动机性能的提高提供指导并且可以降低实验费用,缩短实验时间。33104
关键词 发动机 MATLAB 热力学模型 微分方程
毕业论文设计说明书外文摘要
Title Modeling and simulation of thermodynamics of engine based on MATLAB
Abstract
Based on the zero-dimension hypothesis, a rapid calculation program of thermodynamic model of spark-ignition four-stroke cylinder gasoline engine was written. Final equation were derivated by equations of conservation of mass, energy and the laws of thermodynamic and it was soluted according to the cylinder’s working process with different characteristics. MATLAB program was applied to study the simulation of engine, the changing of main parameters in the cylinder in whole cycle was obtained. This paper focuses on the effection of inlet pressure, ignition time and compression ratio on engine p-v diagrams and thermal efficiency and Engine p-v diagrams and thermal efficiency of different inlet pressure, Ignition time and compression ratio are obtained. The simulation results were compared with experimental results and found it matches the practical results well. The result of the numerical simulation provides the reliable theory basis for the design and improvement of engine. It can guide the development of new engines and enhance the performance of old engine. As a result, you can reduce the experimental expenses and time and also save the massive manpower as well as physical resources.
Keywords Engine MATLAB Thermodynamic model Differential equatios
目 次
1 绪论 3
1.1 文献综述 3
1.1.1 发动机进行计算机仿真技术的背景与意义 3
1.1.2 国内外研究状况 4
1.1.3 常用发动机仿真软件介绍 5
1.2 本课题要研究或解决的问题和拟采用的研究手段(途径) 6
1.2.1 本课题要研究或解决的问题 6
1.2.2 拟采用的研究手段(途径): 6
2 数学仿真模型的建立 8
2.1 本文的技术路线 8
2.2 热力学过程的数学模型 8
2.2.1 建模过程基本假设 8
2.2.2 建模过程微分方程 8
2.2.3 发动机缸内热力过程分析 9
2.3 活塞往复运动的数学模型 13
2.4 燃烧放热过程的数学模型 14
3 仿真程序设计与编程 18
3.1 MATLAB软件介绍 18 基于MATLAB的发动机热力学建模与仿真+源代码:http://www.751com.cn/zidonghua/lunwen_30002.html