【作者】 高静；

【导师】 郭长虹；

【作者基本信息】 燕山大学 ， 机械设计及理论， 2021， 硕士

【摘要】 空间站对接机构对接锁是我国正在建设的永久服役空间站的关键部件,承担着各舱之间对接、分离、转位和再对接等任务,是保证两相邻飞行器紧密相连的核心部件。空间站的设计运行寿命为15年,因此,对接锁必须要能够在工作状态下安全运行15年,针对以上需求,本文围绕对接锁的服役寿命,从对接锁的寿命预测数学模型、有限元仿真分析以及加速性能试验等方面开展研究。(1)对接锁锁紧力传递路径及寿命预测数学模型的建立以永久服役空间站对接机构对接锁为研究对象,根据其工作原理及承载情况结合锁紧力产生机理,分析对接锁受力模型并建立其锁紧力的传递路径;基于力传递路径和对接锁在稳定服役阶段各零部件的性能退化机理建立其长寿命预测数学模型。(2)对接锁寿命预测数学模型求解通过Arrhenius加速模型、材料的蠕变和应力松弛理论对碟簧、钛合金TB2、TC4R以及铝合金7A04材料的应力松弛/蠕变试验数据进行分析,推导其服役条件下的寿命退化方程和各零件在服役周期内的应力松弛值,然后结合有限元方法求得相应零件应力松弛后的等效弹性模量E’,求解对接锁长寿命预测数学模型,得到其锁紧力理论衰减值,为对接锁寿命预测提供理论基础。(3)对接锁锁紧力衰减有限元仿真应用有限元软件ABAQUS,结合对接锁各零部件材料性能试验获得各材料精确的性能参数,进行对接锁的静态特性研究,对锁紧状态下的对接锁进行强度校核并获取初始状态下的锁紧力;根据对接锁各零件在不同服役阶段的性能参数,进行服役周期内对接锁力衰减仿真,迭代求解锁紧力的衰减量,并与数学模型理论求解的结果进行对比,验证对接锁力衰减仿真分析的准确性。(4)对接锁加速性能退化试验分析以温度作为加速应力开展对接锁的加速退化试验,通过高应力水平下的试验数据,基于阿伦尼斯加速模型预测对接锁正常服役条件下的寿命,与力衰减有限元仿真、长寿命预测数学模型求解的结果进行相互校验,为空间站对接机构对接锁寿命预测提供依据。更多还原

【Abstract】 The docking lock of docking mechanism of space station is the key component of the permanent service space station under construction in China.It undertakes the tasks of docking,separation,transposition and redocking between each module,and is the core component to ensure the close connection between two adjacent aircraft.The design operation life of the space station is 15 years.Therefore,the docking lock must be able to operate safely for 15 years under the working condition.In view of the above requirements,this paper focuses on the service life of the docking lock,from the aspects of the mathematical model of the docking lock life prediction,finite element simulation analysis and accelerated performance test.(1)Establishment of mathematical model for transfer path and life prediction of locking force of butt lock Taking the docking lock of docking mechanism of permanent service space station as the research object,according to its working principle and bearing condition,combined with the generation mechanism of locking force of docking lock,the force model of docking lock is analyzed,and the force transfer path of locking force is established;based on the force transfer path and the performance degradation mechanism of each part of docking lock in stable service stage,the mathematical model of long life prediction is established.(2)Solution of mathematical model for life prediction of butt lock The stress relaxation/ creep test data of disc spring,titanium alloy TB2,TC4 R and aluminum alloy 7A04 were analyzed by acceleration theory and material creep and stress relaxation theory.The life degradation equation and the stress relaxation value of each part in the service cycle were solved respectively.Then the equivalent elastic modulus E ’of the corresponding parts after stress relaxation was obtained by combining with the finite element method The mathematical model of lock life prediction is solved numerically,which provides a theoretical basis for the life prediction of butt lock.(3)Finite element simulation of locking force attenuation of butt lock Using the finite element software ABAQUS,combined with the material performance test of docking lock components,the accurate performance parameters of each material are obtained,the static characteristics of docking lock of space station docking structure are studied,the strength of the docking lock in the locked state is checked,and the locking force in the initial state is obtained;according to the performance parameters of each part of the docking lock in different service stages,the service cycle is carried out Through the simulation analysis of the docking lock force attenuation,the attenuation of the locking force is solved,and the accuracy of the simulation analysis of the docking lock force attenuation is verified by comparing with the results of the theoretical solution of the mathematical model.(4)The accelerated degradation test analysis of docking lock The accelerated degradation test of docking lock is carried out with temperature as the accelerated stress.Based on the test data under high stress level,the life of docking lock under normal service conditions is predicted based on the Arrhenius accelerated model.The correctness of the finite element simulation analysis results of force attenuation is verified,which provides the basis for the life prediction of docking lock of space station docking mechanism.更多还原