The relationship between efficiency and power take-off damping in pivoted-cylinder vortex-induced vibration marine current energy extraction

Vortex-induced vibrations can be utilised for marine current energy extraction, however, the relationship between damping and optimal efficiency is yet to be systematically investigated. This study focuses on the amplitude and frequency response of a single pivoted circular cylinder with 1 degree-of-freedom. Using laboratory scale experiments, variable levels of damping were applied to the system as the cylinder was experiencing vortex-induced vibration. Maximum values for efficiencies and RMS power output occurred at the maximum damping ratio tested, ζ = 0.135. This knowledge will support improvements in the design of marine current energy extraction devices based on the pivoted circular cylinder structure