航空学报 > 2002, Vol. 23 Issue (1): 23-27

跪式起落架在武装直升机坠毁过程中能量吸收能力研究(Ⅰ)——数值仿真计算

杨嘉陵1, 吴卫华1, 赵岩1, 涂展春1, 郭光海2, 胡茂和2   

  1. 1. 北京航空航天大学固体力学研究所, 北京 100083;2. 中航二集团直升机设计研究所, 江西景德镇 333001
  • 收稿日期:2001-03-19 修回日期:2001-09-20 出版日期:2002-02-25 发布日期:2002-02-25

ENERGY ABSORBING CAPABILITY OF KNEELING LANDING GEAR FOR NEW TYPE ARMED HELICOPTERS DURING CRASH PROCESS (Ⅰ): NUMERICAL SIMULATION

YANG Jia-ling1, WU Wei-hua1, ZHAO Yan1, TU Zhan-chun1, GUO Guang-hai2, HU Mao-he2   

  1. 1. Solid Mechanics Research Center, Beijing University of Aeronautics and Astronautics, Beijing 100083, China;2. Chinese Helicopter Research and Development Institute, Jing dezhen 333001, China
  • Received:2001-03-19 Revised:2001-09-20 Online:2002-02-25 Published:2002-02-25

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。

关键词: 抗坠毁, 直升机, 起落架, 有限元, 动力学

Abstract:

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.

Key words: crashworthiness, helicopter, landing gear, FEM, dynamics