Multi-functional periodically heterogeneous structures for energy harvesting and vibration attenuation-effects of piezoelectricity and shunting circuits

Abstract

We explore a kind of metamaterial plate structures intended for simultaneous energy harvesting and vibration control. These structures are designed using a periodically perforated piezoelectric plate (the matrix) with elastic inclusions situated in the holes and serving for the resonators. The design options comprise two- and three-phase configurations related to the mechanical connection between the matrix and inclusions. By introducing a singularity—the focal spot created as a defect in the perfectly periodic structure and using the theory of super-cell, an enhanced piezoelectric energy harvester is obtained. It is observed that such a meta-structure serves as a dual-purpose system: efficiently capturing vibrational energy at a focal spot while maintaining the overall vibration attenuation throughout the structure. The band gap analysis based on the Bloch’s wave decomposition theory shows that by concentrating energy and halting vibration propagation, approximately 10 times energy harvesting enhancement and a remarkable 100 dB reduction in vibrations are achieved simultaneously. Besides the passive response of these meta-structures, we consider its extension by an external electric circuit (EC). Such modified configurations enable to exploit ‘actively’ the piezoelectric plate property to transmit the mechanical response between two, or more distant locations. Due to nonlocal interactions introduced by means the controllable EC, we consider optimization of the EC impedance to reduce the vibrations at a selected location of the whole structure without any external energy supply. The computational study discovers perspectives and benefits of designing such active self-powered meta-structures.