An innovative V-shaped piezoelectric energy harvester for wind energy based on the fully fluid–solid-electric coupling

In order to convert galloping-based vibration energy generated by wind flow into electricity more effectively, an innovative piezoelectric energy harvester (PEH) with V-shaped windward wings is proposed and designed to evaluate its performance in this paper. The V-shaped PEH mainly consists of three components: the main cantilever beam made of an aluminum plate, a piece of macro-fiber piezoelectric composite stuck to the end of the main cantilever beam as the key element of energy harvesting, and a pair of V-shaped windward wings as the structure of the bluff body to produce stronger and more regular vortices in wind flow. Wind tunnel experiments are conducted to evaluate its performance of the output voltages, and the results confirm that the angles of V-shaped wings have dramatically affected the behavior of energy harvesting. A pair of 60° angles was confirmed as the optimal angle for this V-shaped PEH, which can achieve the peak-to-peak value of alternating current voltage (VAC-PP) of more than 100 V when the wind velocity is 10 m/s. Subsequently, the fully fluid–solid-electric coupling for this corresponding two dimensional model is simulated by COMSOL Multiphysics, which expounds the mechanism of swing for this V-shaped PEH under the galloping-based vibration, as well as verifies the rationality of the experimental results.