Enhancing/diminishing piezoelectric energy harvesting by adjusting the attachment height

Abstract

The metasurface applied to the piezoelectric energy harvester can change its performance and which consists of the bluff body’s surface and attachments. In this paper, the effect of the height for the staggered spherical attachment and the normally arranged tri-prism attachment (Esp and Etri) on the output of the harvester is investigated. A mathematical model of the energy harvester is developed by using the extended Hamilton’s principle, and the quasi-steady-state assumption is used to obtain the hydrodynamic force. Experiment conducted in the open channel validated the model. The results show that at the velocity of 0.51 m/s, the output of the harvester with Esp of 2 mm is 1.262 mW, which is 51.86 % higher compared to the bluff body without metasurface, while the bluff body is almost static when Etri is 4.5 mm. Which indicates that applying the attachment with the appropriate height can enhance or suppress energy harvesting. Moreover, the vibration frequency of the bluff body is almost unaffected by the metasurface application. The results of this study can be used to optimize the design of piezoelectric energy harvesters or for vibration reduction of structures.