Enhancing wind energy harvesting through two V-shaped attachments and monostable characteristics in the galloping piezoelectric harvester

To enhance energy harvesting efficiency at low wind speeds, this study introduces a novel galloping piezoelectric energy harvester incorporating two V-shaped attachments inspired by a swallowtail. These attachments are affixed to each side of a square bluff body and are designed to optimize aerodynamic forces, thereby initiating and sustaining galloping phenomena at lower wind speeds. Additionally, the device incorporates an adjustable nonlinear monostable characteristic through magnet placement. This adjustment induces a softening effect, allowing for larger vibration amplitudes even under minimal wind conditions. Through potential energy and restoring force analyses, the study assesses the performance benefits of this monostable characteristic in enhancing energy harvesting. Wind tunnel experiments verify that the harvester outperforms its linear counterparts at lower wind speeds by achieving greater vibration amplitudes and higher voltage outputs. The proposed design promises to broaden the applicability of piezoelectric harvesters in low-wind environments, potentially enhancing their utility in sustainable energy solutions.