Harvesting wind energy with bi-stable snap-through excited by vortex-induced vibration and galloping

Scavenging wind energy has been considered to be a promising solution for providing reliable power for sensors and transducers in smart structures. In this study, a novel wind harvesting design is presented, which is based on vortex-induced vibration and galloping. This design consists of a cruciform cantilever beam with three bluff bodies including two square cylinders and a circular cylinder. A tip magnet and two fixed magnets are added to introduce multi-stability. As the air flow passes through, the proposed harvester could begin executing snap-through at low wind speed and sustain this motion over a wide range of wind speed, thus generating a large output. Especially, the coherence resonance could be excited and sustained over a wide range of wind speed, by which the high output voltage can be generated and kept. For validation, the experiments were conducted. The results show that the proposed configuration could give a large output within the wind speed between 2.0 m/s to 7.0 m/s. This proposed structure may provide a new scenario to improve the performance of wind energy harvesting by combining the advantages of multi-stability and flow-induced instability.