Low-frequency broadband vibration attenuation of sandwich plate-type metastructures with periodic thin-wall tube cores

Sandwich structures are widely applied in modern industry such as aerospace, automobile as well as marine structures. However, the vibroacoustic properties of sandwich structures are adversely influenced by low effective mass. In this study, the flexural wave propagation characteristics and vibration mitigation performances of the periodic sandwich plate-type metastructures are investigated. The proposed sandwich plate-type metastructures are constituted of a sandwich plate with periodic thin-wall circular tube cores and periodically attached local stepped resonators. A finite element method combining Solid-Shell coupling numerical method and Bloch theory is presented to calculate the dispersion relations and the displacement fields of the eigenmodes of the infinite periodic sandwich plate-type metastructures. In addition, the acceleration frequency responses and vibration attenuation performances of finite periodic sandwich plate-type metastructures are numerically investigated and compared with the experimental measurements. Furthermore, the influences of geometric parameters on flexural wave band gaps are conducted. Results show that the sandwich plate-type metastructures can yield a low-frequency broad flexural wave band gap, in which the flexural wave propagation is conspicuously suppressed, resulting in significant flexural vibration attenuation. The flexural wave band gap and vibration attenuation performances can be effectively manipulated by designing geometric parameters of the sandwich plate-type metastructures.

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Flexural wave propagation and vibration isolation characteristics of sandwich plate-type elastic metamaterials

Journal of Vibration and Control ◽

10.1177/1077546320942689 ◽

2020 ◽

pp. 107754632094268

Author(s):

Yinggang Li ◽

Huan Zi ◽

Xiong Wu ◽

Ling Zhu

Keyword(s):

Vibration Isolation ◽

Sandwich Plate ◽

Offshore Structures ◽

Geometric Parameters ◽

Band Gaps ◽

Flexural Wave ◽

Wave Band ◽

Thin Wall ◽

Elastic Metamaterials ◽

Plate Type

Sandwich structures are widely used in the fields of aerospace, automobile as well as ship and offshore structures because of their excellent mechanical performances such as lightweight, high specific strength and high specific stiffness. In this study, the flexural wave band gaps and vibration isolation characteristics of sandwich plate-type elastic metamaterials are numerically and experimentally investigated. The proposed sandwich plate-type elastic metamaterials are constituted of local resonant stubs periodically deposited on a sandwich plate with periodic thin-wall aluminium tube cores. An efficient finite element method combined with a solid-shell coupling method and Bloch periodic boundary conditions is presented and validated by experimental measurements to calculate the dispersion relations and the acceleration frequency responses of sandwich plate-type elastic metamaterials. The influences of geometric parameters on the flexural wave band gaps are performed and discussed. Results show that the proposed sandwich plate-type elastic metamaterials can yield flexural wave band gaps in the low-frequency range and show significant performance on the flexural vibration isolation. Moreover, the flexural wave band gaps can be effectively modulated by the geometric parameters.

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Flexural wave propagation in beams with periodically attached vibration absorbers: Band-gap behavior and band formation mechanisms

Journal of Sound and Vibration ◽

10.1016/j.jsv.2012.09.035 ◽

2013 ◽

Vol 332 (4) ◽

pp. 867-893 ◽

Cited By ~ 145

Author(s):

Yong Xiao ◽

Jihong Wen ◽

Dianlong Yu ◽

Xisen Wen

Keyword(s):

Wave Propagation ◽

Band Gap ◽

Flexural Wave ◽

Formation Mechanisms ◽

Vibration Absorbers ◽

Band Formation ◽

Flexural Wave Propagation

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Flexural waves in elastically coupled telescopic metabeams

Journal of Vibration and Acoustics ◽

10.1115/1.4050809 ◽

2021 ◽

pp. 1-28

Author(s):

Rajan Prasad ◽

Arnab Banerjee

Keyword(s):

Wave Propagation ◽

Band Gap ◽

Wave Attenuation ◽

Dynamic Stiffness ◽

Equations Of Motion ◽

Low Frequency ◽

Length Ratio ◽

Beam Equation ◽

Flexural Wave ◽

Constitutive Components

Abstract This paper investigates the flexural wave propagation through elastically coupled metabeams. It is assumed that the metabeam is formed by connecting successive beams with each other using distributed elastic springs. The equations of motion of a representative unit of the above mentioned novel structural form is established by dividing it into three constitutive components that are two side beams, modeled employing Euler-Bernoulli beam equation and an elastically coupled articulated distributed spring connection (ECADSC) at middle. ECADSC is modeled as parallel double beams connected by distributed springs. The underlying mechanics of this system in context of elastic wave propagation is unique when compared with the existing state of art in which local resonators, inertial amplifiers etc. are attached to the beam to widen the attenuation bandwidth. The dynamic stiffness matrix is employed in conjunction with Bloch-Floquet theorem to derive the band-structure of the system. It is identified that the coupling coefficient of the distributed spring layer and length ratio between the side beams and the elastic coupling plays the key role in the wave attenuation. It has been perceived that a considerable widening of the attenuation band gap in the low-frequency can be achieved while the elastically distributed springs are weak and distributed in a small stretch. Specifically, 140% normalized band gap can be obtained only by tuning the stiffness and the length ratio without adding any added masses or resonators to the structure.

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