Design, Modeling, and Experiments of the Vortex‐Induced Vibration Piezoelectric Energy Harvester with Bionic Attachments

Abstract

Since the energy demand increases, the sources of fluid energy such as wind energy and marine energy have attracted widespread attention, especially vortex-induced vibrations excited by wind energy. It is well known that the lock-in effect in vortex-induced vibration can be applied to the piezoelectric energy harvester. Although numerous researches have been conducted on piezoelectric energy harvesting devices in recent years, a common problem of low bandwidth and harvesting efficiency still exists. In order to increase the response amplitude and decrease the threshold wind speed of vortex-induced vibration, a bionic attachment structure is proposed based on the experimental method. In the present work, twelve models are designed according to the size of pits and hemispheric protrusions which are added to the surface of a flexible smooth cylinder. Compared with the smooth cylinder which is taken as a carrier, the harvester with the bionic structure shows stronger energy capture performance on the whole. As the threshold speed decelerates from 1.8m/s to 1 m/s, the bandwidth, on the contrary, increases from 39.3% to 51.4%. Particularly, for the 10 mm pits structure with 5 columns, its peak voltage can reach 47 V, and its peak power can reach 1.21 mW with a resistance of 800 kΩ, 0.57 mW higher than that of the smooth cylinder. Comparatively speaking, the hemispherical projections structure figures with a much more different energy capturing characteristic. Starting from the column, the measured voltage of the hemispherical bionic harvester is much smaller than that of the smooth cylinder, with a peak voltage less than 15 V and a reducing bandwidth. However, compared with the smooth cylinder, hemispheric projections with 3 columns have a better energy capture effect with a measured voltage of 35V, a resistance of 800kΩ, and a wind speed of 3.097 m/s. Besides, its output power also enhances from 0.48 to 0.56 mW.

Recent advancement of flow-induced piezoelectric vibration energy harvesting techniques: principles, structures, and nonlinear designs

“…The influence of surface morphology of bluff bodies has been studied and verified to improve the energy harvesting efficiency. Non-smooth cylinders, having protrusions and pits [33] , metasurface patterns [34] , and grooves [35] , are graphically presented in Fig. 5.…”

“…The results demonstrated that the novel design not only could 16° α Fig. 5 VIV-based energy harvesters with different surface morphological designs [33][34][35] (color online)…”

Influence of Shape and Piezoelectric-Patch Length on Energy Conversion of Bluff Body-Based Wind Energy Harvester

“…Traditional hydroelectric generators and wind turbines, due to the mechanical losses of bearings, have caused lower efficiency during miniaturization [6]. However, the energy harvester based on flow-induced vibration (FIV) is simple in structure and easy to miniaturize and has no rotating parts, which has attracted a large amount of research [7][8][9][10][11][12].…”

Research on the mechanism of drag reduction and efficiency improvement of hydraulic retarders with bionic non-smooth surface spoilers

“…It was found that the bionic structure could reduce the flow velocity around the surface and change the vortex-induced vibration. Scholars have investigated the effect of shark skin denticle geometry on windbreak fence design (Bajsanski, Stojakovic, Tepavcevic, Jovanovic, & Mitov, 2017) and the effect of bionic attachments on piezoelectric energy harvester improvement (Jin, Li, Wang, & Zhang, 2019). Experimental investigations have been conducted on a new type of non-uniform surface cylinder inspired by harbor seal vibrissae to reduce aerodynamic forces and suppress vortex shedding (W. Chen, Min, Gao, Guo, & Li, 2018).…”