Enhanced performance of cutting angle cylinder piezoelectric energy harvester via coupling vortex-induced vibration and galloping

Abstract

This paper proposes a novel flow-induced vibration piezoelectric energy harvester with various cutting angle cylinders (FIVPEH-C), for coupling vortex-induced vibration and galloping as well as improving the energy harvesting efficiency. The conceptual designing of the piezoelectric energy harvester with different cutting angle cylinders is conducted, the theoretical models of fluid–structure-electric multi-physical coupled fields are derived, the aerodynamic parameters are solved by three-dimensional computational fluid dynamics (CFD) simulation, and the experimental prototypes of the harvester system are fabricated. The accuracy of the theoretical model is verified by the experimental results. The flow field reveals the vortex shedding characteristics and mode conversion mechanisms. The cutting angle cylinder bluff body transforms the formation mode, initial shape, and intensity of the vortices at the microscopic level, which in turn affects the shedding mode and distance of the vortices at the macroscopic level. When α = 0° and β = 0°, the maximum output voltage of the FIVPEH-C is 13.36 V, and the enhancement ratio reaches up to 108.01 % over the conventional one, which verifies better harvesting performance. This work provides important guidance for designing more efficient piezoelectric energy harvesters via various cutting angle cylinders.