Galloping is an aeroelastic instability which incites oscillatory motion of elastic structures when subjected to an incident flow. Because galloping is often detrimental to the integrity of the structure, many research studies have focused on investigating methodologies to suppress these oscillations. These include using passive energy sinks, altering the surface characteristics of the structure, actively changing the shape of the boundary layer through momentum injection and using feedback control algorithms. In this paper, we demonstrate that the critical flow speed at which galloping is activated can be substantially increased by subjecting the galloping structure to a high-frequency non-resonant base excitation. The average effect of the high-frequency excitation is to produce additional linear damping in the slow response which serves to suppress the galloping instability. We study this approach theoretically and demonstrate its effectiveness using experimental tests performed on a galloping cantilevered structure. It is demonstrated that the galloping speed can be tripled in some experimental cases.

This article is part of the theme issue ‘Vibrational and stochastic resonance in driven nonlinear systems (part 2)’.

舞动是一种气动弹性不稳定性，当受到入射流时会引起弹性结构的振荡运动。由于疾驰通常有害于结构的完整性，因此许多研究集中在研究抑制这些振动的方法上。这些措施包括使用无源能量吸收器，改变结构的表面特性，通过动量注入和使用反馈控制算法来主动更改边界层的形状。在本文中，我们证明，通过使舞动结构受到高频非共振基极激励，可以显着提高激活舞动的临界流速。高频激励的平均效果是在慢响应中产生附加的线性阻尼，从而抑制了舞动的不稳定性。我们从理论上研究了这种方法，并使用在疾驰的悬臂结构上进行的实验测试证明了其有效性。结果表明，在某些实验情况下，驰the速度可以提高三倍。

本文是主题问题“驱动的非线性系统中的振动和随机共振（第2部分）”的一部分。