A nature-inspired hybrid wind energy harvester based on a fish evasive maneuvering mechanism

초록

This study introduces a nature-inspired hybrid wind energy harvester (HWEH) for micro-scale wind energy harvesting under complex airflow conditions. Conceptually motivated by the wake-mediated flow phenomena observed during the C-start escape maneuver of fish, the proposed system exploits the coupled interaction between transverse and rotational wake galloping to harvest wind energy. Unlike conventional systems, which are constrained by fixed obstacles, the HWEH incorporates dynamic self-adjusting rotational bodies and elastically restrained obstacles to facilitate coupling between passive wake tracking and flow-structure interaction, which broadens the ranges of its energy-harvesting modes and operating conditions. Experimental and numerical results demonstrate that the proposed system achieves a low critical wind speed of 1.55 m/s, which contributes to improved harvesting initiation under low-wind-speed conditions. A systematic optimization of its spatial configuration and bluff-body geometry allows the HWEH to attain an interval-averaged power output of 20.39 mW, which is competitive with respect to similar small-scale wind energy harvesters. A flow-field analysis indicates that the C-start-inspired configuration promotes vortex interaction and aerodynamic instability, thereby improving the system's electrical output performance. Additionally, a multiple-time-delay model is developed to characterize the dynamic coupling between wake evolution and rotational motion. Finally, a dual-source energy-harvesting system integrated with heterogeneous voltage management circuitry is developed to demonstrate the HWEH's utility for emergency lighting applications. The results highlight the potential of nature-inspired wake interference strategies for facilitating lowthreshold wind energy harvesting, providing useful insights for powering distributed sensors and microelectronic devices.

키워드