Electromechanical energy conversion in a piezoelectric porous plate

The mechanical-to-electrical power conversion of a piezoelectric porous plate driven mechanically by thickness-stretch modes has been studied in this article. An analytical solution is derived from the three-dimensional equations of linear piezoelectric porous materials by considering boundary and circuit conditions. As a numerical example, the piezoelectric porous material PZT-7H with 6 mm symmetry is considered. Effects of the driving frequency, electrical resistance, plate thickness, and porosity on output electrical power and efficiency are discussed in detail. Numerical results show that the output power density at resonant frequencies decreases as the porosity increases. The resonant frequency of the piezoelectric porous plate and output power density at the first resonant frequency decrease as the porosity and plate thickness increase. The output power density at the first resonant frequency increases for increasing the electrical resistance. The efficiency decreases as the driving frequency, electrical resistance, and porosity increase. The findings presented in this article are useful for optimization design of the piezoelectric transducers with air voids.