弹性飞机阵风减缓研究

阵风响应减缓可有效抑制飞机由于离散突风和紊流引起的附加过载。以某民机为研究对象,基于飞机结构动力学方程和非定常空气动力学模型,建立弹性飞机在突风作用和控制面偏转联合激励下的开环气动弹性方程。引入坐标变换,建立飞机刚体模态对应的广义坐标与飞行动力学运动变量之间的关系,从而实现气动弹性方程与飞行动力学方程的融合。并以副翼和升降舵为突风减缓控制面。采用俯仰角速率,翼尖加速度和质心加速度作为反馈信号,针对连续突风和离散突风,分别设计相应的控制律。仿真结果表明,减缓系统对翼尖过载、翼根弯矩具有较好的抑制能力。

Research on Gust Response Alleviation of an Elastic Aircraft

The overloads induced by discrete gust and continuous turbulences can be efficiently sup- pressed by introducing the gust load alleviation system. For a civil airplane, firstly, based on the structural dynamic equations and the unsteady aerodynamics model, the open- loop aeroelastic equations of an elas- tic airplane under gust input and the deflection of the control surfaces are established. Secondly, by intro- ducing the coordinate transformation, the relationship between the rigid body modal coordinates and the motion variables defined in flight dynamics is obtained, which results in the integration equations in aero- elasticity and flight dynamics. Besides, the ailerons and the elevators are used as control surfaces to allevi- ate the gust responses. For continuous and discrete gusts, the corresponding control laws are designed, in which the pitching rate, acceleration in wing tip and mass center are used as the feedback signals. The simulation results show that the control system can effectively alleviate the wing- tip overloads and the bending moments at the wing root.