菱形摩托车车架结构性能的技术的分析研究.pdf

I摘要随着摩托车工业的不断发展,人们对摩托车的要求也越来越高。作为摩托车关键部件的摩托车车架,其结构性能直接影响着摩托车的安全性和舒适性。本文以某摩托车车架为例,对其结构性能进行了相关技术研究,内容包括有限元分析、多体动力学仿真、及结构优化设计,以图为以后的车架结构性能研究提供一定的指导目的。本文首先抽取了车架的CAD中面模型,并得到了有限元模型,对车架进行了静强度分析、刚度分析同时提出了分析评价。为更好地考察车架结构的动力学性能,本文进一步作了车架模态分析和模态评价。在有限元分析的基础上,本文为了能够更加准确地分析车架在实际使用中的动态特性,根据摩托车仿真设计的需要以及多体系统动力学研究的成果,建立了摩托车多体动力学仿真模型。模型中将车架作为一个柔性体进行考虑,实现了多体机械系统仿真与有限元分析的更好结合。本文先后研究了车架在怠速和常速行驶两种工况下的动态特性、发动机不同频率下对车架振动的影响和前后悬架各参数对摩托车平顺性的影响。最后本文将结构优化技术引入到车架的分析中,利用尺寸优化技术,以车架各部位所受应力为依据对车架各焊接管进行了厚度优化,使摩托车车架趋向轻量化,同时鉴于车架的刚度和模态振动频率,对车架的局部厚度进行了修改。最后本文对修改后的车架进行了校核,各项指标都有所改善。本文的研究对今后摩托车车架结构性能的技术研究有一定的指导意义,所积累的一些分析数据,为以后相应的工程分析提供了一些参考与指导。关键词:摩托车车架有限元分析多体动力学分析结构优化IIAbstract As the motorcycle industry continues developing, the requirement of the motorcycle has e increasingly high. As a ponent of the motorcycle, the structure performance of motorcycle frame has a direct impact on motorcycle safety fort. This thesis takes a motorcycle frame as an example and makes a research on its structure performance, including the finite element analysis, multi-body dynamics simulation, and structural optimization of design analysis, hoping to provide some guidance to future motor frame analysis. This thesis first takes the mid-surface model from the motor frame CAD data and gets the finite element model. Then, static strength analysis、stiffness analysis and corresponding evaluation were made at the same time. In order to better study the dynamic properties of the frame, the modal analysis and modal evaluation was made in this article. On the basis of the finite element analysis, in order to more accurately analyze the corresponding dynamic characteristics of the frame in the actual use, the thesis establishes the dynamic simulation model of motorcycle in accordance with the needs of motorcycle design and multi-body system dynamics simulation. In the model, a flexible frame body was substituted to rigid frame body to realize bination of the multi-rigid-body mechanical system simulation and finite element analysis.