汽车行驶平顺性建模与仿真

《物流系统建模与仿真》结课论文汽车行驶平顺性建模与仿真

学院：研究生学院

专业班级：机械工程1402班

学生姓名：剑江湖

时间：2015 年5月18 日

摘要

通过分析汽车振动源和人体对振动的反应, 用模态综合技术, 建立了十三自由度人-椅-车系统的动力学模型, 运用随机振动理论, 给出了振动形态、传递函数、悬架动挠度、车轮动载荷、座椅加速度等参量的计算方法, 开发了一套“ 汽车平顺性仿真软件” 并利用已有的汽车数据, 对汽车行驶时的振动特性进行了仿真, 得到了重要结论: 发动机与轮胎刚度、阻尼, 后桥阻尼对驾驶员座椅处的振动影响不大; 驾驶员座椅的垂直刚度增加很大时, 对垂直方向振动响应比较大; 前桥刚度、阻尼对驾驶员座椅处的振动影响较大; 前轮胎刚度对前桥振动影响较大, 前轮胎刚度增加, 则振动加强;后桥刚度对汽车平顺性有一定影响, 后桥刚度减小, 则座椅处垂直加速度减小. 利用该模型可对汽车行驶平顺性进行预测或评估.

关键词: 汽车; 平顺性; 建模; 仿真

Abstract

From the analysis of automobile vibration sources and the human responses to vibration , a mechanic model of man -chair -vehicle system with 13 degrees of freedom is built by vibration pattern analyzing technology .Using the random vibration theory , the calculating methods are developed for parameters , including vibration pattern , transfer function , wheel transient load , and acceleration of seat , automobile ride quality simulation software is developed . With available data of motor , the simulation calculating results about vibration character istics are given ,and important conclusions drawn are as follows : the stiffness and damping of the generator and wheel tire and the damping of back -axis have not much effect on the vibration of the seat ; Vertical stiffness of driver ' s seat has much effect on the vibration as it gets larger ; The stiffness and damping of fore-axis have much effect on the vibration of driver seat . The stiffness of the fore tires has much effect on the vibration of the fore-axis . The vibration increases with the stiffness of fore -tire increasing , The stiffness of back-axis has some effect on the automobile ride quality .As the stiffness of back-axis decreased , the acceleration of the driver ′ s seat decreases . With this simulation software , automobile ride quality can be predicted or evaluated .

Key words : Automobile ; ride quality ; model ; simulation

目录

摘要................................................................................................. I Abstract .............................................................................................. II 目录............................................................................................... I II 第1章绪论 ............................................................................... - 1 -

1.1 课题研究的背景和意义 ................................................ - 1 -

1.1.1 汽车行驶平顺性研究的背景和意义 ................. - 1 -

1.1.2 轿车和重型汽车行驶平顺性研究的意义 ......... - 1 -

1.1.3 汽车行驶平顺性建模与仿真研究的意义 ......... - 2 -

1.2 国内外汽车行驶平顺性建模与仿真研究现状 ............ - 3 -

1.2.1 面向结构和面向参数的方法比较 ..................... - 3 -

1.2.2 路面对汽车激励建模研究的现状 ..................... - 3 -

1.2.3 汽车振动模型建模研究的现状 ......................... - 4 - 第2 章平稳随机振动虚拟激励法研究 ................................... - 5 -

2.1 单点激励单点响应虚拟激励法的基本理论 ................ - 5 -

2.1.1 平稳随机振动的基本假设 ................................. - 5 -

2.1.2 关于单点激励单点响应虚拟激励法的说明..... - 5 -

2.2 广义单点虚拟激励法的基本理论 ................................ - 6 -

2.2.1 结构系统的频率响应 ......................................... - 6 -

2.2.2 广义单点平稳随机激励 ..................................... - 6 - 第3 章平稳随机振动虚拟激励法的应用 ............................... - 7 -

3.1 虚拟路面激励的构造 .................................................... - 7 -

3.1.1 1/2 汽车结构系统的虚拟路面激励................... - 7 -

3.1.2 四轮整车结构系统的虚拟路面激励 ................. - 7 -

3.2 应用实例 ........................................................................ - 8 - 第4章总结 ............................................................................... - 9 - 参考文献...................................................................................... - 10 -