摘要
在简述直升机抗坠毁原理的基础上 ,模拟直升机机体的等效质量与跪式起落架构成的组合系统在 6m/ s硬着陆垂直撞击地面时的塑性动力响应和能量吸收过程。所用的模型为 :1基于真实几何构型和材料特性的起落架 FEM动力学计算模型 ;2简化的弹簧 -刚性杆系统模型。通过 Lagrange方程解出了直升机以6 m/ s的速度垂直撞击地面这一过程的动态响应 ,近似给出了起落架吸收的能量 (塑性功 )占初始动能的百分比 ;机体的动能变化曲线以及主缓冲器的载荷谱曲线。两者结果进行了比较 ,为直升机抗坠毁设计提供理论指导。
Landing gear is one of the key components of armed helicopters during their design. The dynamic behavior of the landing gear, especially its energy absorbing capability, plays an important role in attenuating the impulsive loading and ensuring the survivability of occupants. This paper firstly introduces the basic design principles of helicopter crashworthiness, and then a typical example of a landing gear associated with a fuselage represented by an effective mass system of the rigid truss undergoing the hard landing impact vertically to the ground with a velocity of 6m/s is studied by using two approaches. One is FEM analysis based on the dynamic model and the other is energy absorbing by the landing gear during the hard landing (crash) process; the change of the kinetic energy of the helicopter and the impact curve of the main attenuation oleo cylinder have been given. Furthermore, a comparison between the results obtained from the two approaches is made. The study can be used as a theoretical instruction for the new type of helicopter crashworthiness design.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2002年第1期23-27,共5页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金 ( 19972 0 0 6 )
航空科学基金资助项目
