Metamaterial with mass-stem array in acoustic cavity

Abstract

A vibro-acoustic metamaterial with negative effective mass has been designed and fabricated. This metamaterial consists of an array of wire stems with attached tiny masses in an acoustic cavity. These internal masses contribute to energy absorption near the natural frequencies of the designed structure. This metamaterial damps single resonance of internal mass and has larger mass damping parameter than stiffness damping parameter. Ease of fabrication makes the metamaterial practical for dynamic disturbance mitigation and acoustic attenuation.

Bandgap of flexural wave in periodic bi-layer beam

“…Some achievements have been made in vibration control (Narayanamurti et al., 1979; Liu et al., 2000; Hu and Xu, 2014; Hedayatrasa et al., 2015). More recently, metamaterial, proposed by Veselago (1968) and proved by Pendry (2000), has generated heated discussion in recent years (Smith et al., 2004; Fokin et al., 2007; Islam and Newaz, 2012; Zhu et al. 2014; Pai et al., 2014; Nouha et al., 2015).…”

Design of a multi-resonator metamaterial for mitigating impact force

“…Wang 25 designed a new representative cell of an elastic metamaterial that could generate negative mass and negative modulus by translating and rotating the cell in a controlled manner. As well as the aforementioned theoretical studies, the potential engineering applications of AMs have been widely studied for acoustic attenuation, 26,27 noise control, [28][29][30][31][32][33][34][35] invisibility cloaking, 36 and energy absorption. 37,38 The specially designed microstructure of an AM plays an important role in its performance.…”

Dissipative multi-resonator acoustic metamaterials for impact force mitigation and collision energy absorption

“…In this work, we focus our studies on the attenuation effects of AMs which received substantial attentions in the past, and previous researches on AMs include multiple fields, such as acoustics attenuation [22,23], noise control [24][25][26][27][28][29], invisibility cloak [30] and energy absorption [31,32]. A kind of one-dimensional resonant AM [33] was presented, and its left-handed propagation property of acoustic waves was also demonstrated.…”