非定常气动力对飞行动力学特性影响分析

Impact Analysis of Unsteady Aerodynamic Force on Flight Dynamics Characteristics

在模糊逻辑非定常气动力建模的基础上,研究了非定常气动力对飞行动力学特性的影响。首先分析了非定常气动模型与定常气动模型的差别。其次采用分支分析方法,对带定常与非定常气动模型的飞行动力学系统的陡尾旋状态平衡分支图进行计算、比较与分析,并通过仿真对结果进行验证。研究表明,在大迎角状态下,非定常气动模型与定常气动模型存在较大的差别,对飞行动力学特性将产生一定的影响,需要在大迎角控制律设计中考虑非定常气动力的影响。

Based on the unsteady aerodynamic force modeling with the fuzzy logic method, this paper studies the impact of the unsteady aerodynamics force on the flight dynamics characteristics. Firstly, the differences between the unsteady and the steady aerodynamic models are illustrated. Secondly, with the method of the bifurcation analysis, the equilibrium bifurcation diagram of the flight dynamic system with steady/unsteady aerodynamic model is calculated, compared and analyzed. Conclusions are confirmed by the flight simulation. The result shows that in the high AOA state, there are differences between the unsteady and the steady aerodynamic models and it has a certain influence on the flight dynamics charac- teristics. To design the flight control system, the influence of unsteady aerodynamic forces needs to be considered and evaluated.