Enhanced performance of piezoelectric energy harvester by two asymmetrical splitter plates

This paper proposes a novel vortex-induced vibration piezoelectric energy harvester attached to two asymmetrical splitter plates (VIVPEH-S), which aims at converting the vibration mode from vortex-induced vibration (VIV) to galloping and improving the energy harvesting efficiency. The conceptual designing of VIVPEH-S with two asymmetrical splitter plates under various installation angles is first conducted, the experimental prototypes are then fabricated and the wind tunnel experimental system is constructed, and the simulation model of the harvester system is finally established. The effects of the installation angles of two asymmetrical splitter plates on the vibration characteristics and harvesting performance of VIVPEH-S are experimentally investigated, and the vortex shedding characteristic and mode conversion mechanism are revealed by CFD simulation. The results demonstrate that the installation of the asymmetrical splitter plates changes the vortex shedding characteristics and transforms the vibration mode from VIV to galloping, which can significantly broaden the working bandwidth, and improve the energy harvesting performance. A maximum enhancement ratio of the output power of VIVPEH-S with α = 60° and β = 90° is up to 471.2% over the conventional VIVPEH. This work provides an important foundation for designing a more efficient piezoelectric energy harvester by using asymmetrical splitter plates.