大迎角非定常气动力数学模型研究

Unsteady Aerodynamic Modeling of Aircraft at High Angle of Attack

对建立纵向大迎角非定常气动力模型的状态空间法进行了分析。针对模型形式复杂、待辨识参数过多的问题,提出了减少参数的新模型。新模型保持状态方程不变,简化了输出方程。结果表明,改进的模型简化了辨识过程,可同时表现气动力非线性与非定常的基本特性,准确预测动态气动力。

State space modeling of unsteady aerodynamics for aircraft at high angle of attack is analyzed here. As the existed model is intricate with too many unknown coefficients, a simpler aerodynamic model is developed, which keeps the state equation that using an internal variable descriptive of the flow field unchanged, while with a few coefficient for the output equation. This simpler model describes nonlinearity and unsteady properties of aerodynamics at high angle of attack. The predict results of the model are compared with experimental and CFD calculated force data, results show that the simpler model is rational and feasible.