Structurally-integrated resonators for broadband panel vibration suppression

Abstract

There is limited understanding on interaction mechanisms that govern vibration attenuation when a small coverage of lightweight resonators are applied to practical engineering structures. To shed light on the unknowns, this research investigates lightweight elastomeric half cylindrical resonators attached to an aluminum panel using a small mass ratio around 3% and only around 1.7% coverage over the panel area. Finite element modeling of the system dynamics is complemented by corresponding experimental undertaking. The eigenfrequencies and eigenmodes of the resonators are scrutinized for the respective contributions provided towards broadband panel vibration suppression. The first order eigenmodes of the resonators are found to exert great influence on the starting mode for greater vibration attenuation, which may be tuned by the Young’s modulus of the resonators. The concept of displacement polarization is established to probe how the resonator eigenmodes quantitatively contribute to attenuate the forced panel vibration. This study reveals how flexural panel vibration may be attenuated by transferring the vibration from the panel to resonators by virtue of modal interaction, and prepares a generalized analytical technique that may be used by other researchers studying multi-modal interactions between host structures and applied resonators. These findings may guide the future development of lightweight resonators with a small coverage area for vibration suppression in engineering applications.