具有操纵面间隙非线性二维翼段的气动弹性分析

 基于Theodorsen 理论和Wagner 函数,提出了不可压缩流作用下三自由度二维翼段任意运动非定常气动力表达式。对操纵面自由度具有的间隙非线性,建立了二维翼段气动弹性系统无量纲分段线性运动方程。数值仿真预示了系统极限环振动的相轨迹、无量纲振动幅值和频率,表明操纵面铰链处存在的间隙非线性将导致整个系统的极限环振动;随着来流速度的增加,系统极限环振动的幅值和频率都存在跳跃现象。

Aeroelastic Analysis of a Two-Dimensional Airfoil with Control Surface Freeplay Nonlinearity

Based on Theodorsen's theory and Wagner's function, the expressions of unsteady aerodynamic forces for arbitrary motions of a two-dimensional airfoil with three degrees of freedom are presented. It is assumed that the airfoil is subjected to an incompressible flow. The non-dimensional piecewise linear equations of motion for the two-dimensional airfoil with control surface freeplay nonlinearity are established. The phase trajectories, non-dimensional amplitudes and frequencies of limit cycle oscillation are predicted through numerical simulation. Simulation results demonstrate that the freeplay nonlinearity in the control surface hinge moment can result in limit cycle oscillations of the whole system. With the increase of air speed, the jump phenomenon appears in the amplitudes and frequencies of limit cycle oscillations.