Abstract It is well known that mode localization occurs in the panel flutter structural systems. Therefore, it is reasonable to expect the aeroelastic stability of the structure to be enhanced by changing the geometrical sizes and material properties of the structure along the airflow direction. In this investigation, an axially functionally graded (AFG) cylindrical shell is designed and its super aeroelastic behaviors in supersonic airflow are studied. The enhanced aeroelastic stability and the excellent capability in the passive flutter suppression are achieved by the present AFG design. For the thickness of the cylindrical shell, three types of functions are analyzed. Numerical results show that all these three functions can increase the flutter bound of the cylindrical shell to some extent. It is also noted that in some situations, local mode coalescence happens. In this study, an effective method is proposed to eliminate the local mode coalescence by adding the lumped mass. For the material properties, two groups of functions are considered. It is found that under suitable parameters of the functions, even if the effective stiffness of the whole structural system decreases, the flutter bound of the structure can still be increased due to the AFG design. In addition, the flutter stability of the AFG cylindrical shell is much better than that of the traditional transversely functionally graded shell. The present study is significant in the aeroelastic design of aerospace vehicles.

中文翻译：

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超音速气流中轴向功能梯度圆柱壳的优异气动弹性行为

摘要 众所周知，面板颤振结构系统中会发生模态局部化。因此，通过沿气流方向改变结构的几何尺寸和材料特性来提高结构的气动弹性稳定性是合理的。在这项研究中，设计了轴向功能梯度 (AFG) 圆柱壳，并研究了其在超音速气流中的超气动弹性行为。目前的 AFG 设计实现了增强的气动弹性稳定性和出色的被动颤振抑制能力。对于圆柱壳的厚度，分析了三种类型的函数。数值结果表明，这三个函数都可以在一定程度上增加圆柱壳的颤振边界。还要注意的是，在某些情况下，局部模式合并发生。在这项研究中，提出了一种通过添加集中质量来消除局部模式聚结的有效方法。对于材料特性，考虑了两组函数。发现在合适的函数参数下，即使整个结构系统的有效刚度降低，由于AFG设计，结构的颤振界仍然可以增加。此外，AFG圆柱壳的颤振稳定性远优于传统的横向功能梯度壳。本研究对航天飞行器的气动弹性设计具有重要意义。考虑了两组函数。发现在合适的函数参数下，即使整个结构系统的有效刚度降低，由于AFG设计，结构的颤振界仍然可以增加。此外，AFG圆柱壳的颤振稳定性远优于传统的横向功能梯度壳。本研究对航天飞行器的气动弹性设计具有重要意义。考虑了两组函数。发现在合适的函数参数下，即使整个结构系统的有效刚度降低，由于AFG设计，结构的颤振界仍然可以增加。此外，AFG圆柱壳的颤振稳定性远优于传统的横向功能梯度壳。本研究对航天飞行器的气动弹性设计具有重要意义。