方向舵蒙皮的壁板颤振分析

针对某飞机出现的方向舵蒙皮壁板颤振故障引发的振动疲劳裂纹问题，进行了相关的分析计算和修改方案。利用MSC．NASTRAN软件，建立了计算壁板颤振的有限元模型，取前15阶固有振动模态构建模态坐标系下的颤振方程。选用ZONA51超声速气动力计算程序分析壁板的气动力，采用空气密度折半的方法来模拟壁板单面承受气动力的情况。计算结果表明，方向舵蒙皮发生了壁板颤振。通过对方向舵蒙皮结构修改方案的进一步分析，表明修改方案能够满足壁板防颤振设计的要求，并且具有相当大的安全裕量。

Analysis of Panel Flutter for Aircraft Rudder Skin

It is believed that some dynamic fatigue cracks found on aircraft rudder are caused by panel flutter. In this paper, the finite element approach is adopted to analyze the panel flutter problem for an aircraft rudder skin to probe the reason of its fatigue cracks appeared after some hours of flight. The panel flutter model is established using MSC. NASTRAN, and ZONA51 code is used to calculate supersonic aerodynamics of panel. When using ZONA51 code, the air density is halved to take into account for the situation that airflow only acting on one-side of the panel. Numerical results prove the occurrence of panel flutter on the rudder skin. Further analysis illustrates that by adequate modification of Ref. 1 to the rudder structure, the rudder skin is safe enough from panel flutter, and the dynamic fatigue cracks fault can be eliminated.