【作者】 王文涛；

【导师】 米彩盈；

【作者基本信息】 西南交通大学 ， 车辆工程， 2008， 硕士

【摘要】 发展高速列车技术是当今我国铁路运输的重点,而列车头部外形流线化是改善其空气动力学性能的主要技术手段。为进一步提高我国高速列车研发、设计和制造水平,本文在曲面造型技术、参数化技术的理论基础上,在SolidWorks软件平台和Visual C++编程环境中利用COM组件技术开发出高速列车头部外形参数化CAD系统。高速列车头部外形是形状复杂的空间曲面,对其进行合理的计算机模型表达是进行相关设计、性能分析与计算以及实现CAD/CAM的基础。本文对国内外高速列车气动外形设计及三维曲线曲面造型理论进行了大量研究,分析了高速列车头部外形曲面设计的原则和方法,并选择NURBS曲面造型技术构建流线化的曲面模型。通过对参数化技术及机车车辆行业中CAD应用现状的分析,选用优秀的中端微机三维机械设计软件SolidWorks作为高速列车头部外形参数化CAD系统开发平台。基于对SolidWorks二次开发相关技术的深入研究,选择Viusal C++作为系统开发环境。根据SolidWorks中NURBS曲线便于控制与修改的特点,在特定的水平剖面、横剖面和纵剖面上生成若干控制型线,构建高速列车头部外形基本轮廓的三维线框和光顺的NURBS曲面,实现驱动尺寸及特征属性值的参数化变量设置,建立高速列车头部外形曲面模型库。通过SolidWorks API接口实现DLL插件程序驱动,在人机交互对话框中输入任务书给定的外形轮廓控制参数后,系统调用曲面模型库内的相应模型自动生成外形曲面。基于COM组件技术,在Visual C++中使用ATL和MFC类库进行开发获得的系统具有Windows应用程序风格的菜单、工具栏、形式多样的对话框、大量的信息提示和良好的容错处理机制,功能丰富,操作简单,易于掌握。在完成高速列车头部外形曲面参数化计算机辅助设计的基础上,可对曲面实施等距、加厚和提取任意剖面位置曲面型线的技术处理,可设计相关附属件边界、输出IGES格式文件,从而可以在其它CAD/CAE系统中进行后续的外形及板梁结构设计、强度分析、气动性能分析等工作。系统在高速列车头部外形设计理论的基础上,结合我国机车车辆企业的研发及制造水平,可以大大降低列车外形及结构设计工程师的工作量,提高产品设计效率,缩短研发周期,具有一定的工程实用价值。更多还原

【Abstract】 Developing high-speed train technologies is an emphasis of modern Chinese railway transportation, while the streamlined design of train nose shape is a main technical mean to improve its aerodynamic performance. To further enhance the level of Chinese high-speed train research & development, design and manufacture, a parameterized CAD system for the nose shape of high-speed trains was developed in this paper on the platform of SolidWorks software by using COM technology in the programming environment of Visual C++, which was on the base of surface modeling technology and parametric technology.A reasonable computer model of the high-speed train nose shape which is a complex space surface is the base of performing related designs, performance analysis & calculations and realizing CAD/CAM. In this paper, the design of high-speed train aerodynamic shapes and the theory of surface modeling were widely researched, and the principles and methods for the design of high-speed train nose shape were analyzed, while the NURBS technology was chosen to build the streamlined surface model.Through the analysis of parametric technology and the CAD application state in railway locomotive and rolling stock industry, SolidWorks, which is an excellent software among the mid-range three-dimensional mechanical design on microcomputer, was chosen as the developing platform for parameterized CAD system for the nose shape of high-speed trains. Based on deeply research on the related technologies of SolidWorks application development, Visual C++ was chosen as the developing environment for the system.According to the characteristics that a NURBS curve in SolidWorks is easy to control and modify, a number of control molded-lines were created on the horizontal section, lateral section and longitudinal section. Then the three-dimensional wire-frame and smooth NURBS surface of the high-speed train nose shape basic outline were constructed. After setting the parametric variables of the driven dimensions and the feature property values, the model database of highspeed train nose shape was established. The DLL plug-in program was driven through SolidWorks API interface. Corresponding model will be called from the surface database and the surface shape will be generated after the outline shape control parameters that were given in the specification were typed into the human-computer interaction dialog boxes.The system that was developed in Visual C++ with the ATL and MFC class library has rich functions and easy to operate/learn with the menu/toolbar of Windows program style, all kinds of dialogs, plenty of hints and good fault-tolerant mechanisms. After completing parameterized computer-aided surface design of high-speed train nose shape, the technical treatments of surface offset, surface thicken and molded lines abstraction on any section of the surface can be performed. Related attachment boundaries can be designed, and the files in IGES format can be exported. Therefore followed designs of shape and plate beam structure, strength/aerodynamic performance analysis can be carried out in other CAD/CAE systems.The system, which is based on the design theory of high-speed train nose shape and integrated the research & development and manufacturing level of Chinese locomotive and rolling stock enterprise, can greatly reduce the workload of train shape and structure design engineers, improve the efficiency of product design and shorten the development cycle so that it has a certain practical value in project application.更多还原