Nonlinear dynamic characteristics of the multistable wake-galloping energy harvester

To improve the energy harvesting performance of flow-induced vibration energy harvesters, this paper proposes the design of the nonlinear multistable wake-galloping energy harvester. The corresponding lumped-parameter model is established to use for theoretical analysis. The homoclinic and heteroclinic orbits of nonlinear bistable and tristable wake-galloping energy harvesters are theoretically calculated by using the Padé approximation method providing a foundation for the applying of the Melnikov method. Finally, the threshold value of chaotic motions for the harvester is calculated by using the Melnikov method, and the results are verified by numerical simulations. Overall, this study provides a foundation for theoretically prediction of the chaotic motion of nonlinear flow-induced vibration energy harvesters, and provides guidance for the structural design.