机体柔性对飞机着陆载荷影响的试验与仿真研究

Experiment and simulation research on the effect of aircraft flexibility on landing load

摘要:

由于现代民用飞机新材料新结构的应用增加，机体柔性逐渐增大，着陆过程中机体与起落架系统的耦合不可忽视。为研究机体柔性对飞机着陆载荷的影响，设计含起落装置的整机简化结构，基于模态叠加原理建立刚柔耦合的全机着陆动力学仿真模型，分别开展起落架落震试验及全机落震试验，得到一系列试验数据；通过试验数据验证动力学模型的正确性，并进一步确认分析方法，研究机体柔性对着陆载荷的影响规律。结果表明：起落架动载荷与全机动载荷预计结果与试验值变化趋势相近，峰值误差小于5%；机体柔性对飞机着陆动响应的影响不可忽略，考虑机体柔性后起落架垂向地面载荷峰值将降低，脉宽将增大。

Abstract:

In order to research the influence of aircraft flexibility on landing load, an experiment piece of full scale aircraft simplified structure with landing gears has been designed. Meanwhile, a rigid-flex coupling full aircraft landing dynamics simulation model was established based on the theory of mode superposition.Otherwise, landing gear drop experiment and full scale aircraft drop experiment were carried out respectively. The influence of aircraft flexibility on landing load was further studied through the simulation model, which was verified through the experiment data, and the results show that the experimental method can effectively obtain a series of data such as landing gear vertical load, buffer stroke, and acceleration at the center of gravity. The landing gear dynamics model and full scale aircraft landing dynamics model have an error of less than 5% compared to the experiment, the reliability of the simulation model was verified. The influence of aircraft flexibility on landing dynamic response cannot be ignored. Considering the flexibility of the aircraft, the peak vertical ground load and acceleration at the center of gravity of the landing gear will decrease, the pulse-width of the vertical ground load and the acceleration will increase, and the landing power absorbing and buffering efficiency of the landing gear will decrease. The results provide reference for aircraft weight reduction and landing gear design.