Broadband absorption of ocean wave energy using a graded array of heaving buoys in three dimensions

Abstract

The generation of renewable power from ocean waves at a commercial scale requires arrays of wave energy converters (WECs) to be designed for efficient power capture over broad frequency bands and a wide range of incident wave directions. Here, array designs are developed in a three-dimensional model based on linear potential-flow theory, by arranging heaving-buoy-type WECs into rows, and spatially grading the resonant properties of successive rows via linear spring–damper power take-off (PTO) mechanisms. The grading leverages theories for rainbow reflection and rainbow absorption, and involves analyses of Bloch waves and pole–zero pairs in complex frequency space to inform the array layout a..