Enhancement of aeroelastic energy harvesting from galloping, vortex-induced vibrations and flutter with a beam stiffener

Wireless sensing systems have been widely exploited in structural health monitoring and environmental monitoring systems in order to ensure the integrity and reliability of infrastructures and their operating environment. Due to the continuously reduced power requirement of wireless sensing nodes, harvesting ambient energy to implement self-powered wireless sensor networks has attracted growing research interests. Aeroelastic energy harvesting focuses on converting aeroelastic energy into electricity by exploring aeroelastic instabilities, such as flutter, vortex-induced vibrations and galloping. A conventional aeroelastic energy harvester consists of a piezoelectric composite cantilever connected with a bluff body at its free end. As an alternative to the conventional aeroelastic energy harvester, in this article, we propose an easy but quite effective method to significantly enhance the power generation capability of aeroelastic energy harvester. The method is to attach a beam stiffener to the substrate of the harvester, which works as an electromechanical coupling magnifier. It is shown to be effective for all the three considered types of harvesters based on galloping, vortex-induced vibration and flutter, leading to a superior performance over the conventional designs without the beam stiffener, with dozens of times increase in power, yet with comparative or even smaller transverse displacement.