【作者】 孙岩；

【导师】 王雷；

【作者基本信息】 东北大学 ， 机械工程（专业学位）， 2013， 硕士

【摘要】 据统计,飞机在使用过程中发生的强度问题中80%以上是由疲劳破坏引起的。在飞机中检测到的疲劳裂纹中,孔边的裂纹大约占三分之一。据粗估计,一架大型飞机上约有150万～200万个铆钉和螺栓。因此,开展航空含孔结构件的件疲劳寿命研究具有重要的实际应用价值。含孔结构的疲劳寿命预测过程复杂而艰涩,工程技术人员需要花费大量的精力。分析效率较低,并且分析过程中涉及大量数据,易出现不容易发现的错误。针对以上情况,本文以典型含孔结构为研究对象,在研究了参数化技术、有限元分析方法及疲劳强度等理论和手段的基础上,以MATLAB的GUI为系统的开发平台,使用ANSYS来完成疲劳参量的计算,使用MATLAB的数值计算功能来完成复杂的疲劳寿命计算,并利用ACCESS数据库来管理数据。系统中将几何结构、载荷、材料力学性能的参数输入及最后的计算结果输出集成到一个环境中。本文的主要内容包括：首先,以航空中蒙皮、桁条及框等典型结构为研究对象,依托应力严重系统对结构及受力进行抽象简化,对系统进行功能分析,确定输入输出及需要完成的功能,对系统进行开发,实现了含孔连接板件疲劳寿命准确、快速、方便地预测。其次,以飞行器中典型的耳片结构为研究对象,抽象并简化了几何和受力,运用名义应力法、局部应力应变法及断裂力学法来对耳片结构进行寿命预测。该系统实现了耳片结构的参数化建模,自动调用有限元软件获得应力、应变、应力强度因子等用于疲劳寿命预测的载荷参数；可以实现常幅、程序及随机多种载荷的疲劳寿命预测,可以根据疲劳试验数据自动生成疲劳曲线,自动获取材料的疲劳性能参数。最后,解决了MATLAB、ANSYS及ACCESS三种软件混合编程的若干难题。MATLAB GUI界设计中使用了非系统自带控件；解决了MATLAB与ACCESS、 MATLAB与ANSYS的数据接口问题。APDL编程设计中,解决了任意载荷角下的余弦载荷的加载,任意裂纹长度及角度下全裂纹几何模型的建立及应力强度因子的求解。更多还原

【Abstract】 According to statistics, in the course of the aircraft, more than 80% strength problems are caused by the fatigue damage. Detected in the aircraft fatigue cracks, the hole edge cracks up about one third. According to rough estimates, a large aircraft contains 1.5 million to 2 million rivets and bolts. Therefore, carrying out fatigue life study of typical components containing hole has important practical value. The process of components containing hole fatigue life prediction is complex and abstruse, and engineers need to spend so much time on it. The analysis’s efficiency is low and the process of it needs large amounts of data which is not easily prone to errors found. Thus, this paper regards the components containing hole as the object of study, based on the method of parametric design theory, finite element method and fatigue life theory and so on, and chooses graphical user interface of MATLAB as a development platform, completing the calculation of the fatigue parameters with the ANSYS, performing calculation of complex fatigue life using MATLAB numerical calculation functions, and using ACCESS database to manage data. The system integrates the input of geometry parameters, loading parameters and material properties parameters and the output of the final results into one environment. The main research contents are as follows:First of all, regarding skins, stringers, frames and other typical aviation parts as the object of study, simplifying the forces and structure relying on stress severity factor method, making functional analysis of the system to determine the input and output and the need to complete the function of the system development, achieve the fatigue life accurately, quickly and easily predict.Secondly, regarding lug as the object of study, simplifying the forces and structure, predict the fatigue life by nominal stress, local stress-strain and fracture mechanics method. The system realizes the lug parametric modeling, finite element software is automatically invoked to obtain the stress, strain, stress intensity factor for fatigue life prediction; can achieve fatigue life prediction under constant amplitude, program and random loading, generates fatigue curves based on fatigue test data, automatic access to material fatigue performance parameters.Finally, solve a number of problems of MATLAB, ANSYS and ACCESS mixed programming. MATLAB GUI uses non-system controls. Solve the MATLAB and ACCESS, MATLAB and ANSYS data interface problems. In the design of APDL programming, solve the loading of arbitrary angle cosine loading, establish full crack geometry model under arbitrary crack length and angle and solve the stress intensity factor.更多还原