Analytical and numerical fluid-structure interaction study of a microscale piezoelectric wind energy harvester

In this paper, an analytical approach and two numerical models have been developed to study an energy-harvesting device for micropower generation. This device uses wind energy to oscillate a cantilevered beam attached to a piezoelectric layer for generating electric energy output. The analytical approach and the first numerical model consider the fluid-structure interaction phenomenon in the harvester performance. The equations governing beam oscillations and airflow have been coupled to a set of four differential equations in the analytical approach. This set of equations has been solved to determine the beam deflection and the air pressure variation with time. The numerical methods have been conducted by employing a commercial software. The results of the analytical method and the first numerical model have been compared in different working conditions, and their credibility has been discussed. In the second numerical model, the electromechanical performance of the piezoelectric material has also been incorporated in the harvester device analysis. This model has been verified against experimental data for the output voltage and power of the device available in the literature. Finally, the effect of different geometrical parameters has been studied on the harvester performance, and suggestions have been made to improve the harvester efficiency.