航空学报 > 2002, Vol. 23 Issue (1): 28-32

跪式起落架在武装直升机坠毁过程中能量吸收能力研究(Ⅱ)——理论模型分析方法

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 (Ⅱ): THEORETICAL MODEL ANALYSIS

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:

采用简化的弹簧 -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。与有限元分析结果进行比较,符合程度很好,可为直升机抗坠毁初始设计提供理论指导。

关键词: 直升机, 抗坠毁, 起落架, 理论模型, 动力学

Abstract:

In the previous paper, the finite element method (FEM) was adopted to analyze the dynamic plastic response and the energy absorbing capability 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 an initial velocity of 6m/s.The model is based on practical armed helicopters. During the primary design stage, how to simply and effectively estimate the energy absorbing capability of the helicopter structural components and how to establish the corresponding rule of reasonably distributing the impact energy to the components are extremely important. This paper is focused on the simple theoretical model of using the spring mass system based on Lagrange differential equations to approximately estimate the partitioning of the energy absorbing by the landing gear during the hard landing process. The changes of the kinetic energy of the helicopter and the impact curve of the main attenuation oleo cylinder have been given. Finally, a comparison between the results obtained from the FEM technique and present the oretical model is made.

Key words: crashworthiness, helicopter, landing gear, theoretical model, dynamics