A kind of single degree-of-freedom (SDOF) flutter, which is also called transonic buzz, would appear on the aircraft control surface in a specific transonic state. Engineers deal with control surface buzz mainly by improving the stiffness or damping of the structure. Traditional adjoint-based aerodynamic shape optimizations mainly focus on the aircraft aerodynamic performance. In this paper, the unsteady adjoint method is employed to improve the transonic fluid-structure interaction (FSI) stability from the viewpoint of aerodynamic shape optimization. To achieve this aim, the aerodynamic damping derivative, which represents the work done by flow to structure, is adopted as the objective of shape optimization. Results show that through the airfoil shape optimization, the FSI stability of the control surface is remarkably improved, and the buzz is eliminated successfully in design conditions. In addition, the aerodynamic performance of the control surface is also refined.

一种单自由度（SDOF）颤振，也称为跨音速嗡嗡声，会以特定的跨音速状态出现在飞机控制面上。工程师主要通过提高结构的刚度或阻尼来处理控制面嗡嗡声。传统的基于伴随的空气动力学形状优化主要集中在飞机的空气动力学性能上。从空气动力学形状优化的角度出发，本文采用非稳态伴随方法来提高跨音速流固耦合的稳定性。为了达到这个目的，采用气动阻尼导数作为形状优化的目标，该导数代表通过流向结构完成的功。结果表明，通过机翼形状的优化，操纵面的FSI稳定性得到了显着改善，在设计条件下成功消除了嗡嗡声。此外，操纵面的空气动力学性能也得到了改善。