A piezoelectric energy harvester based on flow-induced flexural vibration of a circular cylinder

This article proposes a new piezoelectric structure for energy harvesting from flow-induced vibrations. It consists of a properly poled and electroded flexible ceramic cylinder. When it is in a flow perpendicular to its axis, the flow exerts a transverse force on the cylinder due to asymmetric vortex shedding, which drives the cylinder into flexural vibrations with an electrical output. A one-dimensional model is derived for the motion of the cylinder, which allows an analytical solution from which the basic behaviors of the energy harvester are calculated and examined. For a cylinder of 40 cm in length and 1cm in diameter in flowing air with a speed of 5 m/s, the output power is of the order of 10(-3)W. It becomes significantly higher if the flow speed is increased.