Experimental Study of a Moored Floating Oscillating Water Column Wave-Energy Converter and of a Moored Cubic Box

Minghao Wu; Vasiliki Stratigaki; Peter Troch; Corrado Altomare; Tim Verbrugghe; Alejandro Crespo; Lorenzo Cappietti; Matthew Hall; Moncho Gómez-Gesteira

doi:10.3390/en12101834

Energies (May 2019)

Experimental Study of a Moored Floating Oscillating Water Column Wave-Energy Converter and of a Moored Cubic Box

Minghao Wu,
Vasiliki Stratigaki,
Peter Troch,
Corrado Altomare,
Tim Verbrugghe,
Alejandro Crespo,
Lorenzo Cappietti,
Matthew Hall,
Moncho Gómez-Gesteira

Affiliations

Minghao Wu: Department of Civil Engineering, Ghent University, Technologiepark 60, B-9052 Zwijnaarde, Belgium
Vasiliki Stratigaki: Department of Civil Engineering, Ghent University, Technologiepark 60, B-9052 Zwijnaarde, Belgium
Peter Troch: Department of Civil Engineering, Ghent University, Technologiepark 60, B-9052 Zwijnaarde, Belgium
Corrado Altomare: Department of Civil Engineering, Ghent University, Technologiepark 60, B-9052 Zwijnaarde, Belgium
Tim Verbrugghe: Department of Civil Engineering, Ghent University, Technologiepark 60, B-9052 Zwijnaarde, Belgium
Alejandro Crespo: Environmental Physics Laboratory, Universidade de Vigo, 36310 Pontevedra, Vigo, Spain
Lorenzo Cappietti: Department of Civil Engineering, Università degli Studi di Firenze - UniFI, Via di Santa Marta 3, 50139 Florence, Italy
Matthew Hall: School of Sustainable Design Engineering, University of Prince Edward Island, Charlottetown, PE C1A 4P3, Canada
Moncho Gómez-Gesteira: Environmental Physics Laboratory, Universidade de Vigo, 36310 Pontevedra, Vigo, Spain

DOI: https://doi.org/10.3390/en12101834
Journal volume & issue: Vol. 12, no. 10
p. 1834

Abstract

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This paper describes experimental research on a floating moored Oscillating Water Column (OWC)-type Wave-Energy Converter (WEC) carried out in the wave flume of the Coastal Engineering Research Group of Ghent University. This research has been introduced to cover the existing data scarcity and knowledge gaps regarding response of moored floating OWC WECs. The obtained data will be available in the future for the validation of nonlinear numerical models. The experiment focuses on the assessment of the nonlinear motion and mooring-line response of a 1:25 floating moored OWC WEC model to regular waves. The OWC WEC model motion has 6 degrees of freedom and is limited by a symmetrical 4-point mooring system. The model is composed of a chamber with an orifice on top of it to simulate the power-take-off (PTO) system and the associated damping of the motion of the OWC WEC model. In the first place, the motion response in waves of the moored floating OWC WEC model is investigated and the water surface elevation in the OWC WEC chamber is measured. Secondly, two different mooring-line materials (iron chains and nylon ropes) are tested and the corresponding OWC WEC model motions and mooring-line tensions are measured. The performance of these two materials is similar in small-amplitude waves but different in large wave-amplitude conditions. Thirdly, the influence of different PTO conditions is investigated by varying the diameter of the top orifice of the OWC WEC model. The results show that the PTO damping does not affect the OWC WEC motion but has an impact on the water surface elevation inside the OWC chamber. In addition, an unbalanced mooring configuration is discussed. Finally, the obtained data for a moored cubic model in waves are presented, which is a benchmarking case for future validation purposes.

Published in Energies

ISSN: 1996-1073 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Technology
Website: http://www.mdpi.com/journal/energies

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