Improving piezoelectric energy harvesting from an aeroelastic system
Our experimental study sought to answer the question: how to maximize the piezoelectric power extraction of an aeroelastic system? A simple rectangular cantilever plate, which experiences non-linear aeroelastic limit cycle oscillations (LCO), was used as a basic vibrating system. The plate was covered entirely with piezoelectric elements on both sides. By adding small discrete masses along the plate, we were able to increase the power generation efficiency by 260% while reducing the airspeed required to produce this power, from 23.5 m/sec to 15.1 m/sec, and the level of vibrations from 77 g to 24 g. Moreover, the energy harvester can be exploited over a wide range of air speeds without structural failure. Our experiments show several surprising results: • With proper mass placement, piezo-elements near the tip of the vibrating plate can generate more power that those near the root. • The increased damping of the system contributes to a more efficient and sustainable power generator. • For a power generator which is based on an elastic structure which experience large deflections, the use of PVDF piezo-elements is advantageous, as opposed to more efficient ceramic based elements. Our goal for this work is to contribute to a more practical piezoelectric energy harvesting solution based on aeroelastic effects.
