Performance Comparison and the Influence of Cross-sectional Shape in Piezoelectric Energy Harvester Using Vortex-induced and Wake-induced Vibration
摘要
To demonstrate the superiority of wake-induced vibration (WIV) in flow-induced vibration piezoelectric energy harvesting, a novel integrated dual-bluff-body piezoelectric energy harvester (PEH) was proposed in this paper. Wind tunnel experiments were conducted to investigate the impact of different cross-sectional shapes on the output performance of the device. The operational mechanism was analyzed using two-way fluid-structure interaction theory. Results show that the integrated structural design not only significantly improved the output performance of the PEH but also facilitated device miniaturization, overcoming the limitations of complex structures and challenges in miniaturization in existing technologies. Compared to vortex-induced vibration, the PEH driven by WIV achieved a 177.2% increase in maximum output voltage and a 66.7% expansion in effective operational range. Among the tested cross-sectional shapes, a circular interference column delivered the best performance under WIV, with maximum output power exceeding that of square and equilateral triangular cross-sections by 60.65% and 44.4%, respectively. Moreover, the second peak in energy conversion efficiency associated with the circular cross-section exhibited a coverage area 2.4 times larger than that of a square cross-section, enabling stable energy output across a broad range of wind speeds. These findings offer important insights into the application of FIV in piezoelectric energy harvesting and provide strong support for the advancement of self-powered technology.