Investigation of Host Structure Compliance in Aeroelastic Energy Harvesting

This paper experimentally investigates the interactions between host structure compliance and natural frequency and the behavior of a fluttering piezoelectric energy harvester. Unlike the base excitation case where a piezoelectric energy harvester extracts energy from a vibrating base structure, the aeroelastic flutter energy harvester generates limit cycle oscillations from an ambient fluid flow. The flow induced oscillatory motion of the energy harvester can transfer energy into the host mounting structure, and may introduce significant vibrations in the structure as well affect the behavior of the energy harvester itself. The energy harvester motion and electrical output is compared for a rigid host structure, as well as a flexible host structure, and the vibrations induced in the host structures are also be examined. The results show significant effects on the energy harvester cut-in wind speed, power output, flutter limit cycle oscillation frequency, and optimal electrical load as a result of the host structure compliance.