基于线性间隙单元的民机舱门破损安全分析  

Fail-safe analysis for civil aircraft doors based on linear gap element

作　　者：吕雄飞 袁强飞[1] 张文斌[1] 权泽芬 LYU Xiongfei;YUAN Qiangfei;ZHANG Wenbin;QUAN Zefen(Shanghai Aircraft Design and Research Institute,Shanghai 201210,China)

机构地区：[1]上海飞机设计研究院,上海201210

出　　处：《民用飞机设计与研究》2022年第3期72-79,共8页Civil Aircraft Design & Research

摘　　要：现代民用飞机的登机门、应急门等舱门多采用半堵塞式方案,这类舱门的部分结构,如导向轴、止动块等,大于门框的净开口尺寸。在承受正压载荷时,舱门止动块和门框止动块接触,同时导向轴和导向槽需要保持足够的间隙以保证增压载荷全部通过止动块传递至机身。在破损安全工况中,当某一止动块破损时,舱门变形可能导致导向轴和导向槽接触从而将一部分载荷传递至机身,显然这取决于二者之间的间隙大小。传统的破损安全分析中多忽略导向轴和导向槽之间的间隙,认为止动块破损后相邻的导向轴一定会承担一部分增压载荷。以某型飞机的半堵塞式登机门为研究对象,使用MSC/NASTRAN的线性间隙单元模拟导向轴和导向槽的初始间隙,对破损安全工况下登机门的受力情况进行分析,结合未考虑初始间隙的分析结果进行讨论,对比结果说明了线性间隙单元在民用飞机破损安全工况分析中的作用,进一步揭示了设计间隙对于载荷分配的影响规律,从强度角度给出舱门关键传力部件的设计依据。The passenger door, emergency door and other doors of civil aircraft are mostly designed semi-plugged, of which some marginal structures, such as guiding shaft and doorstop, exceed the net opening of the door frame. When subject to positive pressure, the doorstops compress the matched stops on the door frame, meanwhile the guiding shaft and the guiding groove should maintain sufficient clearance to ensure that the pressurized load is transferred to the fuselage only through the doorstops. In the failsafe loading condition, since one of the doorstops is damaged, the deformation may make the shaft and the groove contact, thus a portion of load is transferred through the contact which greatly depends on the gap size. The gap is usually ignored in traditional failsafe analysis, and it is considered that the adjacent shaft definitely bears a part of the load after the stop is damaged. In this paper, the failsafe analysis on the semi-plugged door using linear gap element in Nastran as well as the analysis without considering the gap was given, the comparison and discussion demonstrate the significance of using the linear gap in failsafe analysis, and the effect of the design gap on the load distribution was further revealed, the design basis of the key load-carrying components of the aircraft doors was presented from the perspective of mechanics.

关 键 词：半堵塞式 舱门 线性间隙单元 破损安全 

分 类 号：V214[航空宇航科学与技术—航空宇航推进理论与工程]