飞行器MSD结构剩余强度可靠性分析研究  

Residual Strength Reliability of MSD Panel on Aircraft Structure

作　　者：薛小锋[1] 郑香伟[2] 李咪咪[2] 冯蕴雯[1] 

机构地区：[1]西北工业大学航空学院,陕西西安710072 [2]中国航空工业集团公司第一飞机设计研究院,陕西西安710089

出　　处：《西北工业大学学报》2014年第2期195-200,共6页Journal of Northwestern Polytechnical University

基　　金：国家自然科学基金(10577015)资助

摘　　要：飞行器结构的多裂纹是导致结构可靠性降低和破坏的主要原因,在考虑结构多裂纹之间相互影响的基础上对飞行器多裂纹结构进行剩余强度可靠性研究,并探寻影响剩余强度及其可靠性的主要原因。首先通过建立断裂力学有限元模型对飞行器典型MSD(Multiple-Site Damage)壁板结构进行确定性的剩余强度计算;接着在剩余强度和载荷分别服从Weibull分布和正态分布的基础上,建立了MSD壁板的剩余强度可靠性模型;最后通过数值积分对一组2024-T3 MSD壁板进行了剩余强度及其失效概率计算。对比结果显示采用该方法得到的计算结果与试验得到的结构失效概率基本一致。该方法考虑了裂纹间的相互影响、裂纹扩展阻力曲线、剩余强度和载荷的概率分布等方面的因素,可为研究飞行器结构多裂纹现象提供一定的支持。Multiple-crack on the aircraft structure is a major cause the influences adversely structure reliability and integrity. An approach which considers interaction of cracks and stable tearing is employed to calculate the residual strength of Multiple-Site Damage（ MSD） panel. Fracture mechanism finite element model of a certain MSD panel is used to evaluate the residual strength;both fracture toughness and R-curve are considered. On the basis of Weibull distribution of residual strength and normal distribution of load, the residual strength reliability model is developed. Numerical results of 2024-T3 aluminum alloy MSD panels are compared with the test results. The agreement between analysis and experiment is shown to be reasonable. Comparison indicates preliminarily that the proposed approach can give a better prediction and will be useful for investigating MSD panel on aircraft structure.

关 键 词：MSD壁板 有限元 剩余强度 分布 可靠性模型 

分 类 号：O346.1[理学—固体力学]