配重位置对全动舵面颤振抑制效果研究

Effect of balance mass location on flutter of an all-moving rudder

为了研究配重位置对舵面颤振特性的影响,用有限元方法分析了舵面模态,用当地流活塞理论计算非定常气动力,应用Lagrange方程,建立基于模态坐标的颤振运动方程。研究表明:不同位置配重导致不同的颤振边界,放置于前缘与尖弦交点对提高临界动压效果最为明显;在工程设计中,不能简单的以质心前移或者增大扭转-弯曲频率比来指导全动舵面的颤振抑制设计,在前缘与根弦交点附近处加配重使得质心前移,甚至会使临界动压下降;配重通过削弱振型的耦合程度来抑制颤振,配重位置应尽量取在前缘与尖弦交点附近,使得弯、扭振型耦合程度削弱。

Effect of balance mass location on the flutter of an all-moving rudder is investigated. The modes of rudder are analyzed by finite element method. Unsteady aerodynamic force is calculated using local piston theory. The motion equations are established based on Lagrange's equations. Results obtained indicate that, different balance mass locations result in different variations on flutter boundary, the most effective balance mass location on critical dynamic pressure increasing is at the intersection of leading edge and tip chord. Moving mass center toward leading edge or increasing the torsion-bending frequencies radio is not sufficient for flutter suppression of all-moving rudders. Even the critical dynamic pressure will decrease when mass is added to the intersection of leading edge and root chord. By adding mass to proper locations, such as at the intersection of the leading edge and tip chord, the coupled degree of bending and torsion shapes is reduced and results in flutter suppression.