间隙非线性气动弹性颤振控制

Flutter control of aeroelasticity with freeplay nonlinearity

研究了亚音速不可压来流中二元机翼气动弹性颤振主动控制问题.采用Theodorsen准定常气动力建立俯仰方向含有间隙非线性的气动弹性动态方程,然后基于状态依赖R iccati方程推导了非线性颤振控制律.假设只有俯仰角位移和控制面偏转位移可以直接测量,状态空间中的其它变量通过所设计的状态观测器进行了估计.仿真结果显示,观测器可以快速准确地对非直接测量变量进行估计,系统状态变量与控制变量都能够迅速地收敛于零点,表明所设计的控制律可以有效地实现对间隙非线性二元机翼颤振的抑制.

The question of active futter control of prototypical aeroelastic wing section in subsonic uncompressible flow was investigated. The aeroelastic dynamic model with freeplay nonlinearity in pitch was built using Theodorsen quasi-steady aerodynamic force and moment. Then the control law for flutter suppression was derived via state-dependent Riccati equation. For the synthesis of the controller, only pitch angle and controlsurface deflection were measured directly. An observer was constructed to estimate the unavailable state variables of the system. The closed-loop system including the observer and nonlinear controler is asymptotically stable. The simulation results are presented, which show that the observer can give precise estimations for the plunge displacement and the velocities in pitch and plunge, and that the controller is effective for flutter suppression of two-dimensional airfoil with freeplay nonlinearity in pitch.