民机地板以下结构参数变化对复合材料机身适坠性能的影响研究

Influence of Sub-floor Structural Parameters on the Fuselage Crashworthiness of Composite Material Civil Aircraft

为了确保乘员在可生存事故中存活,民机结构必须具备适坠特性。复合材料结构坠撞后的材料破坏形式与常规的金属材料破坏有所不同,复合材料民机的适坠性设计需要对地板以下结构参数变化对复合材料机身适坠特性的影响进行深入的评估。这里对某金属材料民机典型机身结构通过刚度等代设计得到复合材料机身简化模型,利用LS-DYNA3D建立了1/4缩比动力学仿真模型,利用该模型考察了行李舱支柱位置、角度、刚度及行李舱高度变化对复合材料机身适坠性能的影响。仿真结果表明地板以下结构参数变化对复合材料机身和金属机身坠撞响应的影响是不同的,考察的参数中行李舱支柱角度、刚度是影响坠撞响应的关键因素。

The fracture model of composite material aircraft structures is different from metal structures. Therefore, in the crashworthiness design of composite material civil aircraft, it is necessary to investigate the influence of subfloor structural parameters on the crashworthiness of composite material fuselage. The model of a typical composite material civil aircraft fuselage is built from the model of a metal fuselage through equivalent stiffness design, and a 1/4 scale dynamics simulation model based on the simplified composite material structure is built with LS-DY- NA3D, a business finite element software. With the scale model, the influence of the strut location, slope angle, rigidity and the luggage cabin height on the drop and crash properties of the aircraft is studied. The results show that the influence of sub-fioor parameters on the crashworthiness of a composite material fuselage and a metal fuse- lage is different, and the strut slope angle and rigidity are the critical sub-floor structural parameters to influence the crashworthiness of composite material fuselage.