Energy harvesting from vortex-induced vibrations using a pendulum

This paper presents an experimental investigation into energy harvesting from vortex-induced vibrations (VIV) using a pendulum-based arrangement. A series of experiments were conducted in a water channel to examine the effects of flow velocity and applied braking torque on the pendulum shaft. The motion of the pendulum and the fluid loading were measured and analyzed to assess the power output and dynamic response of the system under varying flow and braking conditions. Results indicate that energy extraction is maximized within a narrow range of flow velocities that induce lock-in response, particularly for the highest braking torques that allow motion on the system. A constant (limited) braking torque was applied to evaluate mechanical power at the shaft, and while the braking function was not optimized, the study demonstrates that the system can achieve energy conversion efficiencies comparable to other VIV-based energy harvesting configurations.