シートフラッタ発電機構の基礎検討

抄録

This paper reports numerical simulations of the energy harvester utilizing the flutter phenomenon of a flexible sheet. Especially, we focus on the energy harvester that an electric generator is at the leading edge of a flexible sheet, which is proposed by a preceding study and a simpler device than conventional power generators using flutter. We employ the simple numerical model which is modeled by the finite element method with Absolute Nodal Coordinate Formulation: ANCF and Unsteady Vortex Lattice Method: UVLM to design this energy harvester easily. The equation of motion for a flexible sheet has the Kelvin-Voigt-type material damping and the rotational damping at the leading edge of a sheet to emulate the effect of the coupling between a sheet and the energy harvesting circuit. This model was verified by comparing among experimental results and numerical results obtained by CFD analysis. After that, we searched the appropriate damping coefficient which corresponds to the load of a generator circuit to achieve high harvesting efficiency by the proposed model. As a result, we confirmed that the power obtained from fluid by a weak rotational damper decreases as increase of material damping when inlet flow velocity is large, and increases as increase of material damping when inlet flow velocity is small.