面向复杂构型飞机的非定常气动力建模与辨识

Unsteady aerodynamic modeling and identification for a complicated aircraft configurations

不论是现代高机动隐身战斗机的设计需求还是常规布局飞机的飞行动力学分析,深入研究大迎角飞行时的非线性非定常气动力模型都极其重要。基于纵向运动小振幅及大振幅强迫振荡试验数据,分析了常规稳定导数模型的准确性,并从导数模型出发发展了简化涡流和分离流时间迟滞效应的非定常气动力线性模型和非线性模型,最后应用风洞典型机动历程模拟试验验证了模型的有效性。结果表明:对于复杂构型高机动飞机模型,发展并改进的非线性微分方程模型可以准确预测飞机不同机动下的非定常气动力特性,具有较强的工程可行性。

Adequate modeling of nonlinear and unsteady aerodynamics at high angle of attack flight is important for the design of future fighters with high maneuverability and stealth as well as for the improved prediction of normal aircraft configuration＇s dynamics.The limitations for conventional aerodynamic derivatives model based on longitudinal small amplitude experimental date and large amplitude experimental date at high angle of attack had been analyzed.The dynamic linear and nonlinear aerodynamic model approximating the vertical and separated flow time lag effects is considered along with the conventional aerodynamic model.Using the model the unsteady aerodynamics of one aircraft in typical maneuver simulation tests is predicted.It is suggested that the structural modification of nonlinear differential equation model proposed in this paper is valid in different maneuvers for complicated aircraft configurations,which bears proof on the practicality of the flight dynamics analysis.