Goose Queue Inspired V-Array With Cross-Section Variations for Enhanced Electromechanical Energy Harvesting Behaviors

Leveraging the vortex-induced vibration (VIV) enhancement effect inherent in arrays and the V-formation effect that exists in nature, this article presents a novelty proposition advocating for the utilization of variable cross-section piezoelectric wind energy harvester (PWEH) arrays to improve energy capture efficiency. Initially, this article analyzes of the kinematic and energy capture characteristics of single variable-section bluff bodies, laying the groundwork for assessing array performance. Subsequently, focusing on the kinematic attributes, namely lift and displacement, numerical simulations and analysis are employed to preliminarily verify the VIV enhancement effect. The maximum displacement of the upstream and downstream bluff bodies in the array is 54.0 mm (38.5% higher than a single bluff body) and 33.4 mm (64.5% higher). Following this, the article investigates the output voltage and power of PWEH arrays through free decay experiments and wind tunnel trials, experimentally confirming the VIV enhancement effect. The PWEH array attains a maximum voltage of 28.9 V and power of 0.43 mW. Finally, the energy conversion performance of the VIV enhancement effect is substantiated by comparing the energy conversion efficiency of PWEH arrays. The maximum energy conversion efficiency increases for the upstream and downstream bluff body reaches 1206% and 471.4%, respectively, boosting energy conversion performance significantly.