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Discontinuity, Nonlinearity, and Complexity

Dimitry Volchenkov (editor), Dumitru Baleanu (editor)

Dimitry Volchenkov(editor)

Mathematics & Statistics, Texas Tech University, 1108 Memorial Circle, Lubbock, TX 79409, USA


Dumitru Baleanu (editor)

Cankaya University, Ankara, Turkey; Institute of Space Sciences, Magurele-Bucharest, Romania


Implementation Assessment of a Wave Energy Converter, Based on Fully Enclosed Multi-axis Inertial Reaction Mechanisms

Discontinuity, Nonlinearity, and Complexity 6(4) (2017) 445--463 | DOI:10.5890/DNC.2017.12.004

Ioannis A. Antoniadis$^{1}$, Vasilis Georgoutsos$^{1}$, Andreas Paradeisiotis$^{1}$, Stratis A. Kanarachos$^{2}$, Konstantinos Gryllias$^{3}$

$^{1}$ Mechanical Design and Control Systems Section, Mechanical Engineering Department, National Technical University of Athens, Heroon Polytechniou 9, 15780 Zografou, Greece

$^{2}$ Department of Mechanical, Automotive and Manufacturing Engineering, Faculty of Engineering and Computing, Coventry University, 3, Gulson Road, Coventry, CV1 2JH, UK

$^{3}$ Faculty of Engineering, Department of Mechanical Engineering, Division PMA, KU Leuven, Celestijnenlaan 300, BOX 2420, 3001 Leuven, Belgium

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This paper examines the implementation of a standalone 1 MW Wave Energy Converter (WEC), based on a novel concept of a class of WECs, consisting in fully enclosed appropriate internal body configurations, which provide inertial reaction against the motion of an external vessel. Acting under the excitation of the waves, the external vessel is subjected to a simultaneous surge and pitch motion in all directions, ensuring maximum wave energy capture. The internal body is suspended from the external vessel body in such an appropriate geometrical configuration, that a symmetric four bar mechanism is essentially formed. The first advantage of this suspension geometry is that a linear trajectory results for the center of the mass of the suspended body with respect to the external vessel, enabling the introduction of a quite simple form of a Power Take-Off (PTO) design. The simplicity and symmetry of the suspension geometry and of the PTO, ensure a quite simple and robust technological implementation. Mass and inertia distribution of the internal body are optimized, ensuring maximal conversion and storage of wave energy. As a result, the internal body assembly is essentially, dynamically equivalent to a vertical physical pendulum. However, the resulting equivalent pendulum length and inertia can far exceed those that can be achieved by a simple horizontal or vertical pendulum, suspended or inverted, leading to a significant reduction of the suspended mass.


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