Hybrid piezoelectric-electromagnetic energy harvesting from limit cycle oscillation of the wing

Abstract

As a nonlinear aeroelastic phenomenon, limit cycle oscillation (LCO) of the wing has the potential to supply continuous electrical power output through energy harvesting. In this paper, a basic wing-store structure with hybrid piezoelectric-electromagnetic energy harvesters is proposed to harvest the mechanical energy from bending-torsional coupling LCO response. The nonlinear structure model, the unsteady aerodynamic model and the hybrid energy harvesting model are built and form a piezoelectric-electromagnetic-aeroelastic state-space model. Results show that the extra store at the wingtip can alter the flutter speed and the frequency of the wing. It means that the wing store can lead to LCO response with a higher flutter frequency at lower wind speed. Changing the parameters of the structure and energy harvesting systems can change the intensities and the wind speed range that result in LCO response of the wing. The above features can impact the applicability and electrical power output of the energy harvesting systems. The additional electromagnetic energy harvester can further improve the overall energy conversion efficiency. The details of these effects are demonstrated and the methods for optimizing electric outputs are discussed.