Hydrodynamic and power-capturing performances of a multi-tube oscillating water column device: An experimental study

Abstract

An innovative oscillating water column device with a compact tube array, called the “PILOT” device, is proposed and tested experimentally. The device consists of twelve tubes arranged in two rows and six columns, sharing a common chamber. Regular and irregular wave scenarios with various tube lengths and drafts are employed in the tests. The effects of the relative distance between the tubes, the relative tube draft, and the relative tube length difference on the hydrodynamic, aerodynamic, and energy-harvesting performance of the device model are analyzed. In regular wave scenarios, for various relative drafts and tube length differences, the relative distance between the tubes significantly influences the performance of the device model, with the peak capture width ratio reaching 0.31. In irregular wave scenarios, the average amplitude differences in the free-surface elevation among different tubes, the air pressure variation in the shared chamber, the pneumatic power, and the capture width ratio decrease significantly. The peak capture width ratio is obtained at 0.34. The phase difference between the tubes greatly influences the performance of the shared chamber, which presents opportunities for improvement to enhance the overall performance of the device.