Multi-DOF WEC Performance in Variable Bathymetry Regions Using a Hybrid 3D BEM and Optimization

Eugen Rusu,Kostas Belibassakis,Markos Bonovas

doi:10.3390/en12112108

Eugen Rusu, Kostas Belibassakis + Show 1 more

Open Access

https://doi.org/10.3390/en12112108

Copy DOI

Abstract

In the present work a hybrid boundary element method is used, in conjunction with a coupled mode model and perfectly matched layer model, for obtaining the solution of the propagation/diffraction/radiation problems of floating bodies in variable bathymetry regions. The implemented methodology is free of mild-slope assumptions and restrictions. The present work extends previous results concerning heaving floaters over a region of general bottom topography in the case of generally shaped wave energy converters (WECs) operating in multiple degrees of freedom. Numerical results concerning the details of the wave field and the power output are presented, and the effects of WEC shape on the optimization of power extraction are discussed. It is demonstrated that consideration of heave in combination with pitch oscillation modes leads to a possible increase of the WEC performance.

Highlights

Renewable energy from the oceans is increasingly attracting the interest of the scientific and industrial society
Several aspects related to the performance of wave energy converters of the type of point absorbers are studied, using a boundary element method for solving the associated hydrodynamic problems
A hybrid BEM coupled with a perfectly matched layer model is used for calculating the diffraction and radiation fields, based on information concerning the wave conditions around the floating bodies derived from a coupled mode model

Summary

Introduction

Renewable energy from the oceans is increasingly attracting the interest of the scientific and industrial society. The power efficiency and the operation of the WECs is affected by the bottom topography due to the local entrapped modes and of their impact on the wave propagation, with non-negligible results, especially in array layouts; see [5,8,9]. This is demonstrated in wave propagation over variable seabed topographies or abrupt bathymetries including coastal structures; see, e.g., [10,11]

Objectives

Findings

Methods

Conclusion