翼伞飞行环境复杂多变,常存在阵风与降雨干扰,对翼伞气动性能产生动态影响,造成系统失衡。传统模型忽视翼伞力矩失衡产生的俯仰运动,分析结果误差较大。针对时刻变化的流场环境与翼伞姿态,可借助CFD软件,通过网格速度模拟阵风、离散相模拟降雨、动网格模拟俯仰运动,对非定常Euler方程空间离散求解,得到阵风与降雨对翼伞气动性能的单独影响与耦合影响。利用修正后的翼伞模型进行仿真,结果表明,上述模型能较好描述翼伞气动性能在复杂环境中的变化规律,为翼伞精确建模与归航优化控制提供了参考。
The dynamic effect of parafoil aerodynamic performance is caused by gust and rainfall in the complex and changeable flying environment.While the error of analysis result is large with the ignorance of pitch motion caused by torque imbalance in traditional parafoil modeling.For the changes of flow field environment and parafoil attitude,the unsteady Euler equation is solved by space dispersion with gust simulated by mesh velocity,rainfall simulated by discrete phase and pitch motion simulated by dynamic mesh in CFD technology,witch provides the separate and coupling effect of gust and rainfall on parafoil aerodynamic performance.The regulation of parafoil aerodynamic performance in complex environment is described by modified parafoil model,witch provides the reference for precise modeling and homing control of parafoil.