Optimization of Spacing for Oscillating Wave Surge Converter Arrays Using Genetic Algorithm
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 143, Issue 2
Abstract
The oscillating wave surge converter (OWSC) is a type of ocean wave power device typically consisting of a flap, or arm, hinged at the bottom to allow forward and backward movement by surging waves, and is efficient in generating electricity from waves due to its capability in operating at a wide range of wave spectra. The power generated from the OWSC could be further maximized by arranging the devices in an array at their optimal spacing. This paper addresses the optimization of device configuration within an array by using the genetic algorithm (GA) scheme, for which the spacings between devices are taken as the optimization variables, and the maximum q-factor is chosen as the objective function. The q-factor is a performance assessment parameter that quantifies the average total power produced by an array compared to an individual device. Three array layouts—namely, the single-, double-, and triple-array, each comprising 12 OWSCs—were considered. The pitch response amplitude operator (RAO) of each device in the array was evaluated, from which the power generated and q-factor were determined. The influence of different wave periods and their propagation directions on the array optimal spacing and q-factor was investigated. This study shows that the optimal spacing is highly correlated to the scattering parameter. The results presented here will aid engineers in selecting appropriate spacing that would maximize the power production. The results also provide an enhanced understanding of the performance of the OWSC array when arranged in different configurations.
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Acknowledgments
The authors are grateful for the financial support of the U.K. Engineering and Physical Sciences Research Council (EPSRC) through the EcoWatt2050 Research Consortium (EPSRC reference: EP/K012851/1).
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© 2016 American Society of Civil Engineers.
History
Received: Jan 19, 2016
Accepted: Jul 19, 2016
Published online: Sep 27, 2016
Discussion open until: Feb 27, 2017
Published in print: Mar 1, 2017
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