The major challenge in fixed-wing micro-aerial vehicles (MAV) is their low flight endurance due to energy limitations. A solution might be the design of a piezoelectric harvester to scavenge energy directly from the fluid flow past the MAV. Cantilever beams with a piezoelectric layer undergoing vortex-induced vibrations can convert the mechanical energy available from the ambient environment to usable electrical power. Since a flow-driven piezoelectric composite beam involves three-way coupling between the turbulent fluid flow, the electrical circuit and the structural behavior of the beam, the complexities in modeling and simulation increase sharply. In this work, an efficient three-way coupling algorithm, which links aerodynamics, electrical and mechanical fields has been developed. Aiming to validate the proposed algorithm, a case study was considered, and present numerical simulations were compared with available experimental data. The methodology was applied to an infinite wing and different installation configurations of the harvester were tested at the trailing edge region of the wing. The results have shown that a harvester mounted over the wing surface extracts more energy from the wake, leading to larger oscillation amplitudes and higher power output.

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