【作者】 黄江；

【导师】 关富玲；

【作者基本信息】 浙江大学 ， 结构工程， 2005， 博士

【摘要】 可动部件包含的范围很广,本文主要针对两种类型的可动部件进行研究:(1)空间太阳望远镜成像镜调焦机构;(2)开启式屋盖结构及其可动部件。 本文研究内容所覆盖的学科领域相当多,它包含机构设计、结构设计、力学分析,包括接触分析、带间隙的振动分析等,本文将这些研究内容有机结合在一起,形成了一套有自身特点、比较实用的可动机构设计和研究体系,具有独特创新性。 空间太阳望远镜成像镜调焦机构的设计是在国家“863”高科技课题中展开的,本文的工作是根据改进型设计模型,利用ANSYS软件进行了空间动力环境校验,并以带有间隙的非线性振动系统为研究背景,提出了间隙元法在可动部件中的应用,对于其基本理论只给出推导过程,具有一定的理论意义和实用价值。 空间可动机构一个显著的特点就是构件可动,这表明构件之间必然存在着间隙,在某些情况下,间隙对可动结构的影响非常大。文中给出了间隙元法在空间可动机构接触问题中的应用,推导了其几何边界条件和力学边界条件,利用虚功原理推导了含间隙元弹性接触问题的有限元方程式,给出了其数值解法的迭代步骤,并指出了利用间隙单元进行分析的特点。 开合屋盖结构可以使建筑物同时具有室内和室外两个使用功能,已经成为现代体育建筑的宠儿。目前国际上已成功建成数十座各类型的开合屋面建筑,为当地带来了很好的经济和社会效益,也为开合屋面结构的研究和发展提供了很好的工程实践经验。而我国对开合结构的研究还处于起步阶段,相应的有参考价值的工程资料也很有限。随着经济和技术的发展,我国对于开合屋盖结构尤其是大型开合结构的需求将不断增大。因此对这种结构进行深入的研究刻不容缓,而研究的关键即在于其可动部件。 本文将主要利用Kalker三维弹性体非赫兹理论,分析研究可开启屋盖中行走机构台车轮轨滚动接触的几个影响因素,对滚动接触横向影响系数进行修正,并计算结果进行比较分析。表明蠕滑力受结构变形(主要是轨道翻转变形)的影响很大。往往土木结构变形在量级上大大超过机械结构变形,想要建立精确的行更多还原

【Abstract】 There are two kinds of mechanism included in the research of this dissertation. One is the adjustment mechanism of the imaging lens’s focal length of a space solar telescope, the other is retractable roof structure. Based on the particularities of the space mechanism, much meaningful work has been done in this paper.The work of the adjustment mechanism is a project which is supported by the state committee of "863". Based on a advance model, the space dynamic environment test has been done, and the gap element method is presented on the background of nonlinear vibration system.The effects of clearances within the connections of the mechanisms and of elastic compliance of the links and members of the device are very serious. Especially to the mechanism worked in space environments, the analysis method is important. The gap element method is proposed in the paper for two kinds of problems, which include contact problem and gap joint problem. Elasticity contact problem falls into the category of unknown boundary value problems. It follows that the contact area and contact conditions or states (sticking, sliding or clearance) can never be determined without special mathematical analysis, which is a very difficult work. The boundary conditions of the contact surfaces are deduced. According to the principle of virtual work, the finite element equations of the contact problem composed of gap elements are obtained. The calculating procedure with gap element method and the features of it are all presented. The analysis of parts of the adjustment mechanism made by our lab is given using gap element method. The application of the gap element method in gap joint mechanisms is proposed. The stiffness matrix of the rotate joint elements and sleeve joint elements with gap elements are formed and the dynamic equation of the structure is given in the paper.Retractable roof structure lets building have indoor and outdoor using functions. It is so wildly used in modern sport facilities. There are tens of retractable roof buildings constructed inthe world. They have brought about considerable social and economical benefits. These typical realized retractable roof buildings provide us with great references to further research.The research of retractable roof structures is only at the beginning in China. There are still short of systemic and theoretical guides. With the development of the economy and technology, the requirements of the retractable buildings grow rapidly. Undoubtedly, it is very urgent to do research on the subject. The key point of this research is in its mechanism.The Kalker’s theory of three-dimensional elastic bodies in rolling contact with the Non-Hertzina form is employed to analyze the relationships of creep forces and creepages of retractable roof structure’s running device. The relations is applied to determine the influence coefficients expressing the relations between the lateral elastic deformations of wheelset and track and the lateral unit loads on the contact areas of wheel/rail. The influence coefficients were used to revise some of the influence coefficients, and the theory of Kalker and the modified theory were respectively employed to analyze creep forces of wheelset and track. The numerical results obtained show a great influence of structures deformations of track on the creep forces.The plane stress theory is applied to analyze the contact stress between wheel and rail. The formulas for calculating contact stress and contact region width are derived. The condition of plane strain does not fulfill.The research of retractable roof structure’s wind pressure and wind-induced dynamic response is also been done. The difference of wind pressure distribution between open state and close state is presented. Wind-induced dynamic response analysis with gap element is employed.更多还原