基于ansys的圆柱直齿轮接触应力分析 - 图文

丽水学院2012 届学生毕业设计

基于ANSYS的圆柱直齿轮接触应力分析

机械设计制造及其自动化 机自08 指导老师

摘 要

根据轮齿齿廓的数学模型,在ANSYS环境下建立了轮齿平面有限元模型,并进行了应力分析计算.与传统的方法相比,有限元分析法能准确地获得齿轮的真实应力场,为齿轮强度计算提供了可靠的依据.

通过实例阐述了直齿轮的建模方法,并介绍了具体的设计原理,将生成的一对齿轮进行标准安装生成啮合模型。通过ANSYS转化成由节点及元素组成的有限元模型,运用完全牛顿-拉普森方法进行接触应力的静力学求解,并介绍了算法原理。说明了新的接触单元法的精确性、有效性和可靠性。 关键词： 齿轮 Ansys 接触应力 接触分析 有限元

Based on the ANSYS spur gear contact stress analysis

Abstract

According to the mathematic model of a tooth profile of gear,the finite element model of a flat of gear tooth was established under the environment of ANSYS and the stress of a gear tooth was analyzed and caculated by means of finite element method. The real stress field of gear obtained by finite element method was more accurate than that obtained by traditional method.Therefore,it can provide the dependable basis for strength calculation of teeth of the gear.

The method of modeling of spur gear is illustrated by an example. The concrete design principles are introduced as well.A constructed pair of gears is fixed normatively to give birth to gear model. By way of ANSYS,the gear model is transformed to the finite element model consisting of nodes and elements. Then NR method is used to get the statics solution by contact stress,and the arithmetic principle is introduced. The new contact element method proposed in the thesis is proved to be precise,valid and reliability. Keyword:

gear Ansys contact stress contact analysis finite element

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目录

第一章 绪 论 ........................................................................................................................................... 1

1.1 研究的意义............................................................................................................................... 1 1.2 CAE软件简介.......................................................................................................................... 1 1.3 本设计的主要内容 ................................................................................................................... 2 第二章 有限元法及ANSYS概述 .......................................................................................................... 3

前言 ................................................................................................................................................... 3 2.1 有限元法简介........................................................................................................................... 3

2.1.1 有限元法的基本思想 .................................................................................................... 3 2.1.2 有限元法的特点 ............................................................................................................ 4 2.2 有限元法基本概念和原理 ....................................................................................................... 4 2.3 ANSYS的发展及现状 ............................................................................................................ 5 2.4 ANSYS分析的基本过程......................................................................................................... 7

2.4.1 前处理............................................................................................................................ 7 2.4.2 加载并求解 .................................................................................................................... 8 2.4.3 后处理............................................................................................................................ 8 2.4.4 误差分析........................................................................................................................ 8 2.5 ANSYS几何建模概论 ............................................................................................................ 9 2.6 基本参数设置......................................................................................................................... 10

2.6.1 单元属性...................................................................................................................... 10 2.6.2 网格划分...................................................................................................................... 12 2.6.3 边界条件和载荷的施加 .............................................................................................. 13

第三章 接触问题有限元分析 ................................................................................................................ 15

3.1 接触问题分类......................................................................................................................... 15 3.2 接触单元 ................................................................................................................................ 15

3.2.1 点-点接触单元 ............................................................................................................ 15 3.2.2 点-面接触单元 ............................................................................................................ 15 3.2.3 面-面接触单元 ............................................................................................................ 16 3.3 接触分析步骤......................................................................................................................... 16 第四章 在Pro/e环境下三维建模 ......................................................................................................... 17

4.1 在Pro/e环境下对齿轮建模 .................................................................................................. 17

4.1.1 创建过程...................................................................................................................... 17 4.1.2 Pro/e中3D模型 ......................................................................................................... 19 4.2 装配 ........................................................................................................................................ 20 第五章 齿轮接触应力的Ansys有限元分析 ...................................................................................... 21

5.1 设定分析作业名和标题 ......................................................................................................... 21 5.2 定义单元类型......................................................................................................................... 21 5.3 定义材料属性......................................................................................................................... 23 5.4 3D模型导入 ........................................................................................................................... 24 5.5 对实体划分网格 ..................................................................................................................... 24 第六章 以片体代替实体分析 .............................................................................................................. 26

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6.1 导入2D齿轮外形ansys中建模 ........................................................................................... 27 6.2 对齿面划分网格 ..................................................................................................................... 30 6.3 定义接触对............................................................................................................................. 30 6.4 定义边界条件并求解 ............................................................................................................. 34

6.4.1 施加位移边界 .............................................................................................................. 34 6.4.2 施加第一齿轮位移载荷及第二个齿轮位移边界 ...................................................... 35 6.5 软件计算 ................................................................................................................................ 37

6.5.1 计算内容...................................................................................................................... 38 6.5.2 计算结果收敛批示 ...................................................................................................... 38 6.6 计算的理论分析 ..................................................................................................................... 39 6.7 计算结果分析......................................................................................................................... 41

6.7.1 查看von Mises等效应力 ........................................................................................... 41 6.7.2 查看接触应力 .............................................................................................................. 42 6.7.3 接触应力集中点分析 .................................................................................................. 43

第七章 总 结 ....................................................................................................................................... 44 致 谢 ............................................................................................................................................... 45 参 考 文 献 ........................................................................................................................................... 46

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