Low-frequency vibration suppression of a multi-layered elastic metamaterial shaft with discretized scatters

Abstract

With the aim to reduce the total structural weight, this paper presents a novel radial multilayered elastic metamaterial (EM) shaft in which the scattering layer is circumferentially discretized into several arc-shaped sections with rotational symmetry. The dispersion relations and frequency-response-functions (FRF) of a finite structure are determined numerically first with different discretized geometries. To illustrate the mechanisms of band gaps, the eigenmodes were extracted and analyzed together with dispersion relations and FRF. The results show that in contrast to conventional multi-layered EM shafts, the proposed EM shaft with the weight being reduced by 34% can still yield broadband gaps at low-frequencies and by properly selecting the discretized geometry the band gap ranging from 139 to 197Hz exists for all three elastic wave modes. The results presented in this paper demonstrate a potential design strategy in stabilized shaft engineering.

A brief review of metamaterials for opening low-frequency band gaps

“…The first application of metamaterials, therefore, is to suppress the vibration propagation along the engineering structures based on the band gaps. It is found that the vibration can be attenuated by more than 20 dB in the frequency range of the band gap [80,83,105,107,[118][119] . Due to the remarkable performance of vibration attenuation, metamaterials have been introduced into the vibration isolation floating raft to improve the vibration attenuation and acoustic stealthy performance of underwater vehicles [120] .…”

Metamaterials and their applications: An overview

“…Li et al 66 designed a six-layer radial metamaterial shaft with arched layers, as shown in Figure 68. They extracted the eigenvalues of the system and determined the frequency response and dispersion curves by using the numerical method.…”

Passive Multi-Layer Composite Damper of Flat Belt Tensioner Idler

“…Moreover, passive dampers can involve particles [11,12], periodic sandwich plates [13,14], a honeycomb structure of cells filled with circular carbon tubes forming a composite sandwich structure [15], or a damping layer that can be formed from open-cell foam [16]. The whole structure can be designed as a novel advanced material, e.g., a radial multilayered elastic metamaterial shaft in which the scattering layer is circumferentially discretized into several arc-shaped sections with rotational symmetry [17].…”