A study of vortex-induced energy harvesting from water using PZT piezoelectric cantilever with cylindrical extension

The energy of water flow exists everywhere and it can drive the piezoelectric energy harvester to vibrate to generate electricity. This paper presents an upright vortex-induced piezoelectric energy harvester (VIPEH), inspired by the vortex-induced vibration (VIV) of cylinder in flowing fluid. This harvester consists of a PZT cantilever with a cylindrical extension. Energy harvesting ability of the VIPEH is investigated theoretically and experimentally. An Euler-Bernoulli distributed parameter model as the available electromechanical model for the energy harvester is established. The optimum load resistances R (100-150 kΩ) are obtained for various water velocities. The maximum output power is 84.49 μW with 60.35 mW/m² energy density at the resonance vibration velocity of 0.35m/s. The experimental results are in good agreement with the numerical results. Further, both influences of the cylinder diameter and mass on the energy harvesting ability are investigated. The results show that the VIPEH can achieve better energy harvesting performance from water flow with a lighter weight mass and a larger diameter of the attached cylinder.