摩托车右侧曲轴箱实体建模（本科毕业论文设计）.doc

摘 要
JS400ATV发动机是建设工业集团生产的沙滩越野摩托车装配的发动机，该车主要出口欧美国家，但就其的通过噪声较大，经道路通过噪声实验，发现该发动机噪声是该车型的主要噪声源，且初步发现该发动机的曲轴箱壳体在运行过程中存在共振现象，为进一步证实该机曲轴箱壳体存在共振，有必要对该曲轴箱进行理论模态分析，为此需要对该曲轴箱壳体进行三维建模。目前，工程上主流建模软件建模软件为Catia，UG NX，Pro/Engineer，Solidworks等。我建此模型选用Pro/Engineer。由二维图纸分析，该曲轴箱体主要是壳体，其余为加强筋，柱体，孔等。壳体部分主要是有多个曲面相交。除了草图外，常用的命令为拉伸，挖孔，增厚，倒圆角，扫描，拔模，修剪，混合，合并，偏置等命令。通过对该曲轴箱模型的建立，可以使自己掌握模型建立的基本过程和方法，为并为下一步的仿真分析打下基础。
对壳体进行模态分析，理论模态分析过程中用ANSA进行几何清理。再导入MSC.PATRAN /NASTRAN进行定义和计算而得到。实验模态和理论模态作比较。
关键词：曲轴箱，壳体，三维建模，Pro/Engineer，模态分析







ABSTRACT
The JS400ATV engine is assembled on beach cross-country motorcycle produced by JianShe industry group. It mainly exports to Europe and the United States. But there’s a bit of yawp when ridded. We found out that the engine noise is the main noise source analyzed by riding experiment and there is resonance phenomenon in its crankcase carapace when running. To prove the resonance in crankcase carapace, it is necessary to make its 3D-model. At present, the primary 3D-models for engineering are Catia，UG NX，Pro/Engineer，Solidworks and so on .Because of powerful function in CAD，CAE，CAM and integrate design, analysis, manufacture, it’s popular among design company and it is being used in Machine, automobile, shipbuilding and aviation industry. I choose Pro/Engineer to make 3D-model. Knowing from 2D- drawing, the crankcase mostly consists of carapace plus rib, pillar, hole and so on. The carapace is intersected and thickened by many surfaces. Except drawing, the common orders are “pad”,“hole”,“thicksurface”,“edgefilet”,“sweep”,“split”,“trim”,“union trim”, “offset” and so on. I come to master the basic ways and process to build 3D-Model by building this model, and set up the base for emulator.
ANSA is used to pretreat the model on the theoretic modal analysis,and then import to the MSC.PATRAN / NASTRAN to defined and calculat.thus we gain modal analysis results. At last,we compare the results between the theoretic modal analysis and experiment modal analysis.
Key words：crankcase, shell part ，3D-model, modal analysis，Pro/Engineer

目录
摘 要 I
ABSTRACT II
目录 III
1 绪 论 1
1.1研究的背景及其意义 1
1.2国内外建模的主要工具和现状 2
1.3 PRO／ENGINEER功能模块介绍 4
1.4 MSC.NASTRAN简介及应用 14
1.5主要研究内容和曲轴箱建模方法 14
1.6本章小结 15
2 右曲轴箱壳体模型的建立 16
2.1主壳体部分的建立 16
2.1.1创建主体拉伸 17
2.1.2通过拉伸创建突台部分 22
2.1.3创建突台 23
2.2孔槽部分的建立 25
2.3抽壳和拔模 28
2.4创建其他结构 31
2.4.1创建突台的结构 31
2.4.2创建装配孔 33
2.4.3创建曲轴箱内部结构 35
2.4.创建下图结构，其二维视图如下 36
2.4.5创建一个拉伸 37
2.4.6创建下边视图的结构 37
2.4.7拉伸装配孔 38
2.4.8曲轴箱内部的结构 40
2.4.9创建加强筋结构 41
2.4.10再构建一个加强筋 45
2.4.11建立装配的拉伸 47
2.5突台机构 48
2.6现在构建一个油道 52
2.12本章小结 57
3．右曲轴箱盖模态分析 58
3.1右侧变速器箱盖理论模态分析 58
3.2右侧变速器箱盖实验模态分析 60
3.3本章小结 64
致 谢 65
参考文献 66