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http://dx.doi.org/10.9765/KSCOE.2020.32.4.242

Correlation of Reflection Coefficient and Extracted Efficiency of an Oscillating Water Column Device in Front of a Seawall  

Cho, Il Hyoung (Department of Ocean System Engineering, Jeju National University)
Kim, Jeongrok (Department of Ocean System Engineering, Jeju National University)
Publication Information
Journal of Korean Society of Coastal and Ocean Engineers / v.32, no.4, 2020 , pp. 242-251 More about this Journal
Abstract
In this study, the extraction efficiency and reflection coefficient by a two-dimensional OWC (Oscillating Water Column) WEC (wave energy converter) installed in front of a seawall was investigated for regular/irregular waves. The matched eigenfunction expansion method (MEEM) based on the linear potential theory was applied as an analytical tool. The diffraction problem by the incident wave in the open-chamber and the radiation problem by the oscillating pressure in the closed-chamber were solved to obtain the volume fluxes at the internal free-surface. Applying the volume fluxes into the continuity equation for the airflow in a chamber, we got the oscillating air pressure. The maximum extracted power and corresponding reflection coefficient were determined at the optimal turbine coefficient that maximizes the extracted power. OWC device designed for a high extracted efficiency simultaneously contributes to reduce reflected waves.
Keywords
oscillating water column; wave energy device; matched eigenfunction expansion method; irregular waves; reflection coefficient; efficiency;
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