Relations for a periodic array of flap-type wave energy converters

TL;DR

This paper models the wave interactions with a periodic array of flap-type wave energy converters, revealing how resonance can enhance energy capture and providing relations to optimize farm power output.

Contribution

It introduces a new asymptotic analysis for flap-type wave energy arrays, showing how resonance effects can be exploited for improved energy extraction.

Findings

Resonance of transverse modes can significantly increase energy capture.

Derived relations enable optimization of wave farm power output.

Array of flap converters can outperform line of buoys in energy extraction.

Abstract

This paper investigates the interaction of plane incident waves with a wave farm in the open ocean. The farm consists of a periodic array of large flap-type wave energy converters. A linear inviscid potential-flow model, already developed by the authors for a single flap in a channel, is considered. Asymptotic analysis of the wave field allows to obtain new expressions of the reflection, transmission and radiation coefficients of the system. It is shown that, unlike a line of heaving buoys, an array of flap-type converters is able to exploit resonance of the system transverse modes in order to attain high capture factor levels. Relations between the hydrodynamic coefficients are derived and applied for optimising the power output of the wave farm.