Vibration energy harvesting enhancement of a plate interacting with subsonic airflow in a narrow gap

Abstract

In this study, the vibration energy harvesting of a plate interacting with subsonic airflow in a narrow gap by using a giant magnetostrictive-piezoelectric (GMP) energy harvester is investigated. To improve the performance of the energy harvesting, the effects of the instability and the dynamic bifurcation of the plate on energy harvesting performances are studied. The GMP harvester is integrated in the nonlinear energy sink (NES-GMP) to harvest the vibration energy concentrated by the NES. The equations of motion of the system are derived by using the Hamilton principle based on the nonlinear plate theory and the incompressible airflow model. The model of the subsonic airflow in a narrow gap is established with fourth degrees of freedom by the linear potential flow theory. The stability of the plate is analyzed by monitoring the natural frequencies of the system, and the dynamic bifurcation properties of the plate are analyzed by the Poincaré maps and the bifurcation diagrams. The simulation results show that the harvested energy from the instability state of the plate is more significant than that from the stable state. The variation of the harvested energy when the plate changes from the stable state into the divergence is larger than the variation of the harvested energy when the plate changes from the divergence state into the flutter state. Furthermore, the periodic-n motions can enlarge the harvesting performance significantly but the quasi-periodic motions and the chaotic motions have little effect on the improvement of the harvesting performance.