【作者】 王伟戈；

【导师】 罗虹；

【作者基本信息】 重庆大学 ， 车辆工程， 2006， 硕士

【摘要】 有限元法是一种有效的数值计算方法，运用有限元法对摩托车车架进行分析可以有效的指导和修正设计。但是应用有限元法对摩托车车架进行分析，是一项综合性的工作。要掌握摩托车车架有限元分析方法，首先必须熟悉有限元软件和分析过程，还要对力学和有限元理论有较深的理解，这对于普通的设计人员来说无疑是很大的障碍，也就势必影响到我国摩托车企业自主研发能力的提高。因此，开发摩托车车架有限元分析的专用模块成为我国摩托车企业的迫切需求。 本文在总结摩托车车架结构有限元分析的基础上，应用VB和ANSYS二次开发工具APDL(ANSYS Parametric Design Language)开发出了摩托车车架结构分析系统。系统通过用户输入的几何模型和参数生成建立摩托车车架的有限元模型的LOG文件。用户将这些LOG文件导入ANSYS完成摩托车车架结构分析。本系统包括模态分析、静强度分析、瞬态分析和疲劳强度分析四个模块。运用本系统，用户只需通过简单的填写菜单就可以完成摩托车车架的静强度分析、模态分析、瞬态分析，并据此对车架进行疲劳寿命估算。 论文中通过对几何模型规定坐标系，给出力学模型的简化要求，将不同厚度的零件分组处理，将待划分梁单元的线单独处理，实现了系统有限元模型的自动建立。从而减轻了摩托车车架有限元前处理工作的技术难度和工作量。论文运用建立多个弹簧阻尼单元类型的方法，解决了ANSYS与关键字文件的接口问题。采用节点耦合的方式来模拟铰链连接，用扭转弹簧阻尼单元来模拟铰链摩擦解决了ANSYS/LS-DYNA模块没有铰链单元的问题。 本文还运用本系统对具体的摩托车车架进行了分析计算，通过与手工分析结果的对比，证明本系统是可行的、正确的。 在此基础上，归纳总结了利用VB和ANSYS二次开发工具APDL进行ANSYS二次开发的基本方法和过程，为ANSYS二次开发工作提供借鉴。更多还原

【Abstract】 Finite Element Method (FEM) is an effective numerical analysis method. Analyzing motorcycle frame by FEM can direct and amend design. But it is a composite work to analyze motorcycle frame by FEM. To be master of this work, first you should be familiar with FEM software and FEM analysis process; second you should have profound comprehension about Mechanics and FEM theory. So it is a hard obstacle for general designer. Therefore developing an appropriative module for motorcycle frame intensity FEM analysis is active demanded by native Motorcycle Corporation.Motorcycle intensity analysis system was designed basing on summarizing the FEM analysis of motorcycle frame by VB and ANSYS second development language, APDL (ANSYS Parametric Design Language). The consumer imported the parameter and geometry model to the system. Then the LOG files which build the motorcycle frame FEM model was created by the system. This System includes four modules: modal analysis, static stress analysis, transient analysis and fatigue intensity analysis. Customer can accomplish modal, static and transient analysis easily by filling in some menu. Based on this, a fatigue life of motorcycle frame was estimated.The coordinate system and simplification request of the geometry model were stipulated. Different thickness parts were disposed group by group and the lines perpetrated to mesh were disposed individual. Then the FEM model of motorcycle frame was created automatically by the system. Therefore the technical difficulty and quantity of building motorcycle FEM model was alleviated. The interface problem between ANSYS and DYNA K file was settled by building multi spring damper element type. The gemel joint was simulated by node couple. The friction between gemels was simulated by torsion damper element. Therefore the gemel element that ANSYS/LS-DYNA lacks was simulated preferable.Finally a concrete motorcycle frame was analyzed using the system. A contrast between system analysis result and former manual analysis result was presented. The system was proved feasible and correctBased on the system design, the basic method and process of ANSYS second development by VB and APDL was summarized. It is a reference for ANSYS second development.更多还原