Effects of Higher Order Terms in Aeroodynamic Foroce on the Nonlinear Response of a Galloping PZT Energy Harvester

In this paper, the effects of higher order terms in aerodynamic force model are investigated on the response of galloping piezoelectric energy harvesters. The system comprised a PZT beam with a bluff body and exposed to a fluid force. First, the dimensionless governing elec-tromechanical equations are provided. To model the aerodynamic force, the 3rd and 7th order galloping models are used by adopting quasi-steady assumption. Then, the dynamic response based on the 3rd and 7th order aerodynamic force models are studied, using a numerical inte-gration method. Besides, an approximate-analytical solution based on the multiple scales method (MSM) is provided. Next, the mechanical and electrical response of the system are obtained using the MSM solutions. Finally, the optimum electrical power and the correspond-ing dimensionless load resistance is obtained. The results revealed that considering higher order terms in aerodynamic force expansion is necessary for accurate characterization of the mechanical and electrical responses

Keywords:

PZT energy harvesting , Galloping oscillations , Multiple scales method , Nonline-ar vibrations