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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。
In order to study the effect of counterweight position on the flutter characteristics of rudder surfaces, the rudder surface modal was analyzed by finite element method. Unsteady aerodynamic forces were calculated by the local flow piston theory. Lagrange equation was established to establish the flutter equation based on modal coordinates . The results show that different positions of counterweight lead to different flutter boundaries, and the most obvious effect of improving the critical dynamic pressure is the most obvious when it is placed at the intersection of leading edge and sharp point. In engineering design, it is not easy to move forward with centroid or increase torsion-bending frequency In order to guide the design of flutter suppression at full moving rudder surface, adding weight to the vicinity of the intersection of the leading edge and the root causes the mass center to move forward and even reduce the critical dynamic pressure. The counterweight restrains the flutter by weakening the coupling of mode shapes , The weight position should be taken in the vicinity of the leading edge and the tip of the sharp intersection, making the bending and torsional vibration coupling weakened.