Acoustic energy harvesting based on a planar acoustic metamaterial

TLDR

The study proposes a novel acoustic energy harvester that uses a defected acoustic metamaterial integrated with piezoelectric material. The device confines strain energy from acoustic waves in resonant defects of the AMM, then converts it to electricity using piezoelectric material, with numerical simulations validating its operation. Simulations demonstrate the harvester can generate up to 1.3 V and 0.54 μW/cm³ at 2257.5 Hz, indicating potential for energy harvesting and low‑frequency acoustic insulation.

Abstract

We theoretically report on an innovative and practical acoustic energy harvester based on a defected acoustic metamaterial (AMM) with piezoelectric material. The idea is to create suitable resonant defects in an AMM to confine the strain energy originating from an acoustic incidence. This scavenged energy is converted into electrical energy by attaching a structured piezoelectric material into the defect area of the AMM. We show an acoustic energy harvester based on a meta-structure capable of producing electrical power from an acoustic pressure. Numerical simulations are provided to analyze and elucidate the principles and the performances of the proposed system. A maximum output voltage of 1.3 V and a power density of 0.54 μW/cm3 are obtained at a frequency of 2257.5 Hz. The proposed concept should have broad applications on energy harvesting as well as on low-frequency sound isolation, since this system acts as both acoustic insulator and energy harvester.