Experimental and Theoretical Study on Energy Harvesting Performance of Galloping-Based Energy Harvester Using Rotationally Oscillating Blade

The Hydro-VENUS is an energy harvester exploiting the flow-induced oscillation of a pendulum-like blade. In this study, the effects of the angular amplitude and non-dimensional flow velocity on the energy harvesting performance of the Hydro-VENUS are investigated through water channel tests. A semi-elliptical cross-section blade with the cross-sectional aspect ratio of 6 is employed in these tests. The experimental results revealed that the maximum power coefficient is obtained at specific angular amplitude and non-dimensional flow velocity. The approximate solution for the power coefficient is theoretically provided considering non-linearity of hydrodynamic forces acting on the blade. This theoretical approach revealed that the power coefficient is determined by tip speed ratio of the blade and the maximum power coefficient is obtained at specific tip speed ratio.