操纵面对跨声速机翼气动弹性特性的影响

Effect of Control Surface on Aeroelastic Characteristics of Transonic Airfoil

运用基于非定常CFD的气动力辨识技术,得到跨声速非定常气动力降阶模型。耦合结构动力学方程,建立了基于状态空间的跨声速气动弹性分析模型。分析了典型三自由度二元机翼的颤振边界,分析结果与CFD/CSD直接耦合方法吻合。然后研究了操纵面结构参数(固有频率和重心位置)对跨声速气动弹性特性的影响。研究发现,一些传统的结构设计准则和颤振排除技术未必适用于跨声速状态;操纵面偏转模态常常成为诱发跨声速颤振的主要模态;经典的质量平衡技术可能会降低跨声速气动弹性系统的稳定性。

Based on the aerodynamic identification technique in which the unsteady CFD is used, the unsteady aerodynamic reduced order models （ROM） are constructed. Coupled with the structural equations, the models for transonic aeroelasticity in state space are got. A Mach number flutter trend of a typical airfoil section with a control surface is analyzed and the results obtained agree well with those with CFD/CSD direct coupling method. Then the effects of the structural parameters （natural frequency and the flap static unbalance） of the control surface on the transonic flutter system are studied. Some traditional structural design rules are found to be unfavorable for transonic flutter problem. For transonic flutter problem, the flap pitch mode always becomes a leading mode of aeroelastic system. The traditional technology of mass static unbalance maybe reduces the stability of transonic aeroelasticity.