Acoustic Energy Harvesting From Sonic Crystals with Non-square Lattices Using Piezoelectric Patch

Abstract

Energy harvesting from the environment has been one of the important challenges for researchers in recent years. Acoustic energy is one of the natural sources of mechanical energy that can be converted into electrical energy by using metamaterial or piezoelectric. In such a way that by creating a defect in a regular lattice of the crystal, at the point of defect, the concentration of sound pressure was created, and by installing the PVDF piezoelectric patch, mechanical energy can be converted into electrical energy. In this research, to identify a suitable model to harvest maximum acoustic energy, the effect of various lattices including circular, rhombus, rectangular, square-rhombic, square-rectangular, and rhombus-rectangular lattices on the sound pressure level (SPL) and energy harvesting was investigated. Also, the effect of changing the position of the defect and increasing the number of defects on the SPL was studied. The simulated results were calculated using Comsol Multiphysics 6.0. The validation of the results was confirmed by comparing them with the results of previous studies. The results showed that a square-rhombic lattice can provide the highest SPL and consequently the highest harvested energy. In the square-rhombic lattice, by using the optimal resistance of 15 kΩ at the frequency of 4220.4 Hz, the voltage and power were 11.34 mV and 4.15 nW, respectively.