设计简介
摘 要
汽车车架作为汽车关键的承载部件，它将发动机和车身等总成连成一个有机的整体，承受着来自道路及各种复杂载荷的作用，而且汽车上许多重要总成都是以车架为载体，因此设计出重量轻且各方面性能达到要求的车架结构是一项重要工作。传统的车架结构设计是采用类比的思想进行经验设计，车架的这种设计模式导致的问题包括两个方面：一是车架简化计算精度不够，为保证强度及刚度要求而使车架的设计过于安全，造成设计出的车架结构过重，增加了设计成本；二是造成车架的设计与计算分离，不利于提高车架设计人员的设计水平。设计出的车架结构除了个别部位的应力水平比较高外，大部分部位的应力水平较低。因此，有必要采用有限元法对车架结构进行优化设计，以降低车架的重量，减少汽车的制造成本，提高市场竞争力。
本文以解放J4R中型载货汽车车架为研究对象，在现有CAD图纸的情况下进行简化，通过对ANSYS软件的学习，以Pro/E软件创建车架实体模型，对车架的静力以及模态进行了分析。得到一些有益的结论，并掌握了一般静力分析中的网格划分、约束加载、分析求解等过程进行了认真的学习，为车架的设计和改进提供了指导作用。
关键词：中型载货汽车；车架；ANSYS；静力分析；模态分析
ABSTRACT
As an important component, frame carrying the whole vehicle, such as assembly, take the engine and body together into an organic whole,endure the loads from the road and many kind of complex loads, and many important assemblys are based on frame,use the frame as a vector. So design a lightweight and all aspects of performance to meet the requirements of the frame structure is an important work. The frame structure of traditional design is the idea of experience with analog design, this methed caused two problems: First, simplify the calculation accuracy of the frame is not enough to ensure the strength and stiffness requirements of leaving the frame design is too safe, resulting the frame structure designed overweight. Second is caused by separation of design and calculation of the frame, the frame is not conducive to raising the level of the designer's design. In addition to the frame structure designed for individual parts of the stress level is relatively high, most parts of the stress level low. Therefore, it is necessary to use finite element method to optimize the design of the frame structure to reduce the chassis weight, reduce vehicle manufacturing costs, improve market competitiveness.
In this paper, use FAW J4R medium truck frame for the study, in study of ANSYS software ,and use Pro / E software to create solid models of the static frame and the mode were analyzed. Get some useful conclusions, and mastery of the general process of static analysis for improved frame design and provide guidance.
Key words: MediumTruck ;Frame;ANSYS; Static Analysis; Modal Analysis
目 录
摘 要 I汽车车架作为汽车关键的承载部件，它将发动机和车身等总成连成一个有机的整体，承受着来自道路及各种复杂载荷的作用，而且汽车上许多重要总成都是以车架为载体，因此设计出重量轻且各方面性能达到要求的车架结构是一项重要工作。传统的车架结构设计是采用类比的思想进行经验设计，车架的这种设计模式导致的问题包括两个方面：一是车架简化计算精度不够，为保证强度及刚度要求而使车架的设计过于安全，造成设计出的车架结构过重，增加了设计成本；二是造成车架的设计与计算分离，不利于提高车架设计人员的设计水平。设计出的车架结构除了个别部位的应力水平比较高外，大部分部位的应力水平较低。因此，有必要采用有限元法对车架结构进行优化设计，以降低车架的重量，减少汽车的制造成本，提高市场竞争力。
本文以解放J4R中型载货汽车车架为研究对象，在现有CAD图纸的情况下进行简化，通过对ANSYS软件的学习，以Pro/E软件创建车架实体模型，对车架的静力以及模态进行了分析。得到一些有益的结论，并掌握了一般静力分析中的网格划分、约束加载、分析求解等过程进行了认真的学习，为车架的设计和改进提供了指导作用。
关键词：中型载货汽车；车架；ANSYS；静力分析；模态分析
ABSTRACT
As an important component, frame carrying the whole vehicle, such as assembly, take the engine and body together into an organic whole,endure the loads from the road and many kind of complex loads, and many important assemblys are based on frame,use the frame as a vector. So design a lightweight and all aspects of performance to meet the requirements of the frame structure is an important work. The frame structure of traditional design is the idea of experience with analog design, this methed caused two problems: First, simplify the calculation accuracy of the frame is not enough to ensure the strength and stiffness requirements of leaving the frame design is too safe, resulting the frame structure designed overweight. Second is caused by separation of design and calculation of the frame, the frame is not conducive to raising the level of the designer's design. In addition to the frame structure designed for individual parts of the stress level is relatively high, most parts of the stress level low. Therefore, it is necessary to use finite element method to optimize the design of the frame structure to reduce the chassis weight, reduce vehicle manufacturing costs, improve market competitiveness.
In this paper, use FAW J4R medium truck frame for the study, in study of ANSYS software ,and use Pro / E software to create solid models of the static frame and the mode were analyzed. Get some useful conclusions, and mastery of the general process of static analysis for improved frame design and provide guidance.
Key words: MediumTruck ;Frame;ANSYS; Static Analysis; Modal Analysis
目 录
Abstract II
第1章 绪论 1
1.1 选题的背景 1
1.2 选题的目的 1
1.3 选题的意义 1
1.4 研究现状 2
1.5 课题主要内容 4
第2章 有限元基础及ANSYS软件介绍 5
2.1 有限元分析简介 5
2.2 有限元方法的基本求解过程 6
2.3 有限元分析的误差及建模准则 7
2.4有限元分析软件ANSYS简介 9
2.4.1 ANSYS的发展概述 9
2.4.2 典型的ANSYS分析过程 10
2.4.3 ANSYS的主要功能 11
2.4.4 ANSYS的主要特点 12
2.4.4 ANSYS软件提供的分析类型 13
2.5 本章小结 14
第3章 车架有限元模型的建立 15
3.1 车架的实体建模 15
3.1.1 Pro/E软件简介 15
3.1.2 Pro/E软件基本功能 16
3.1.3 几何建模的简化 16
3.2 应用Pro/E软件三维几何模型的建立 18
3.3 应用ANSYS软件对车架模型进行网格划分 19
3.4 实体单元Solid 45的简介 21
3.5 本章小结 24
第4章 车架有限元的静力级模态分析 25
4.1 车架静力分析 25
4.1.1 车架受力情况 25
4.1.2车架结构静力分析及约束处理 26
4.2 车架模态分析 33
4.2.1 结构动力性能分析方程 34
4.2.2 车架结构模态分析 34
4.2.3 分析结果 41
4.3 本章小结 41
结论 42
参考文献 43
致谢 44
