货台空投系统出舱过程研究(英文)

Extraction Phase Simulation of Cargo Airdrop System

研究了空投系统的出舱阶段中货台与地板接触模型,采用动力学分析方法建立了统一的出舱运动模型。根据试验设计条件开展系统仿真计算,结果与试验数据基本一致。探讨了货台离机过程对离机后俯仰姿态的影响。使用离机时间评价出舱过程对货台空投精确度的影响, 得到了无量纲离机时间的简化算法以方便工程应用;引入了安全距离参数来评价出舱过程安全性,分析了牵引比、质心位置系数和空投时飞机姿态与离机时间和安全距离的关系,为空投系统中货台布局和牵引伞设计等提供了参考依据。

To study the characteristics of cargo extraction, the initial phase of airdrop process, a high fidelity and extendibility simulation model with uniform motion equations for all states during extraction is developed on the basis of dynamics methods and contact models between cargo and aircraft. Simulation results agree well with tests data. Cargo exit parameters, which contribute to cargo pitch after extraction, are studied. Simplified computation model of dimensionless exit time is developed and used to evaluate the relation between extraction phase and landing accuracy. Safe interval model is introduced to evaluate the safety of extraction process. Also, relations between initial parameters, including pull coefficient, aircraft pitch and CG coefficient, etc, and result parameters, including exit time, cargo safety, pitch, etc, are developed to help design of airdrop system, especially the selection of extraction parachute and cargo deployment.