无减摆器旋翼桨叶气弹稳定性分析

Aeroelastic Stability of Damperless Rotor Blade

无减摆器旋翼具有桨毂结构简单、桨毂气动阻力小、桨毂维护简便等优点,但取消了桨毂减摆器后必须确保桨叶在摆振方向有足够的阻尼以保证桨叶的摆振稳定性。基于气弹耦合的方法是实现无减摆器旋翼桨叶摆振稳定性的一个有效方法。建立了无减摆器无铰式旋翼桨叶带有预锥角、下垂角、后掠角和预扭角等结构参数的非线性气弹动力学模型,利用伽辽金方法把桨叶偏微分运动方程简化为非线性常微分平衡方程和关于平衡位置的小扰动运动方程,分析了桨叶的气弹稳定性并进行了参数影响分析。数值结果表明,合理的桨叶结构参数和气弹耦合可确保无减摆器旋翼桨叶在摆振方向的气弹稳定性。

The damperless rotor has the advantage of the hub with simple structure, small aerodynamic drag and easy maintainance. However, without blade lag damper, the blade must have sufficient damping in the lag direction to ensure lag stability. And the aeroelastic coupling based method can approach that effectively. Therefore, the nonlinear aeroelastic dynamic model is established for the damperless and hingeless rotor blade with structural parameters of pre-cone angle, pre-droop angle, sweep angle and pre-twist angle. By using the Galerkin method, the partial differential equations of motion are simplified to the nonlinear ordinary differential balance equations and the small perturbation equations for the equilibrium positions. The blade aeroelastic stability and the parameters effects are analyzed. The numerical results show that reasonable structural parameters and aeroelastic coupling of blade can ensure the aeroelastic stability of damperless rotor blade in the lag direction.