摘 要
汽车工业发展到今天，汽车车身已成为影响其各种性能的最大组成部分之一，特别是轿车车身，它在很大程度上决定了汽车的商品价值和销售市场。近几十年来，人们对汽车的安全性、舒适性、经济性、可靠性和耐久性的要求越来越高；由于能源的紧缺和激烈的汽车市场竞争，又迫使汽车要实现轻量化并尽可能降低成本，因而引发材料工程与制造业巨大的变化，并促使设计理念和设计方法不断改进。有限元法是关于连续体的一种离散化的数值计算方法，亦即在力学模型上近似的数值方法，它在车身结构分析中发挥着重要的作用。
本论文利用先进的CAE技术，以某轿车白车身为主要研究对象，在Hyperworks软件下，建立了轿车白车身详细有限元模型，进行白车身自由模态分析、扭转工况和弯曲工况下的白车身刚度分析，以检测白车身是否满足基本的模态刚度要求。并利用CAE软件进行白车身钣金件的优化，以达到轻量化的目的，提高白车身的经济性和安全性，满足市场需求。
关键词：白车身 模态 刚度 Hyperworks 优化
备注：因要遵循公司保密条约，本论文数据已处理。
I
Modal and Stiffness Analysis and OPtimizationon Body-in-white
of Car Based on Finite Element Method
Abstract
Automobile industry development today, the body has become the various properties of the largest part of the car body, in particular, it largely determines the value of the goods and the sale market of automobile. In recent decades, the vehicle safety, comfort, economy, reliability and durability of the increasingly high demand; because of the shortage of energy resources and the car market with intense competition, and forced the car to lighten and reduce costs as much as possible, and thus lead to materials engineering and manufacturing industry tremendous changes, and make the design concept and design method of continuous improvement. The finite element method is a kind of continuum discrete numerical calculation method, the mechanics model to approximate the numerical method,the body-in-whit structure analysis plays an important role.
In this paper, the use of advanced CAE technology, to body-in-whit as the main research object, in Hyperworks software, establish the detailed finite element model of body-in-whit, for white body free modal analysis of torsional and bending condition and working condition of BIW stiffness analysis of body-in-whit, to detect whether meet the basic modal stiffness degree requirements. And the use of CAE software for white main body sheet metal parts optimization, has reached the goal of lightening the body-in-whit, improve the economy and safety of, meet market demand.
Key words:Body-in-whit Moda Hyperworks Stiffness Optimization
目 录
中文摘要 .................................................................................................................................. Ⅰ 英文摘要. ................................................................................................................................. Ⅱ
II
目 录 .................................................................................................................................. Ⅲ 第一章 绪论 .............................................................................................................................. 1 1.1引言 ................................................................................................................................... 1 1.2国内外车身CAE技术研究现状 ..................................................................................... 2 1.3本文的主要内容 ............................................................................................................... 3 第二章 有限元法理论 .............................................................................................................. 4 2.1引言 ................................................................................................................................... 4 2.2有限单元法和白车身刚度的基本原理 ........................................................................... 4 2.2.1有限元和模态分析基本理论 ...................................................................................... 4 2.2.2白车身扭转刚度基本理论 .......................................................................................... 5 2.2.3白车身弯曲刚度基本理论 .......................................................................................... 7 2.2.4白车身门窗开口变形理论 .......................................................................................... 8 第三章 某轿车白车身有限元建模 .......................................................................................... 9 3.1引言 ................................................................................................................................... 9 3.2建模要求 ........................................................................................................................... 9 3.2.1网格标准的确定 .......................................................................................................... 9 3.2.2网格质量要求 .............................................................................................................. 9 3.3建模的基本步骤 ............................................................................................................. 10 3.3.1建模原则 .................................................................................................................... 10 3.3.2单元类型的选择 ........................................................................................................ 10 3.3.3连接方式的选择 ........................................................................................................ 10 3.3.4单位制及材料特性 .................................................................................................... 11 3.2.5模型的装配 ................................................................................................................ 11 第四章 轿车白车身模态分析 ................................................................................................ 13 4.1白车身模态分析的意义 ................................................................................................. 13 4.2白车身模态分析的基本设置 ......................................................................................... 13 4.3白车身模态分析结果分析 ............................................................................................. 13 4.4本章小结. ........................................................................................................................ 16 第五章 轿车白车身刚度分析 ................................................................................................ 17
III
基于有限元的白车身模态刚度CAE分析及其优化
