Hydrodynamic Performance of Two Types of Floating Breakwaters Integrated With a Wave Energy Converter

Abstract

Two asymmetric types of floating breakwaters integrated with a wave energy converter (WEC-FBs), a floating square box with a triangle (trapezoidal type) or a wave baffle (L type) attached to its rear side, have been proposed. In this research, the hydrodynamic performance, including capture width ratio (CWR), wave transmission coefficient, heave motion, and force coefficient, were studied and compared between the two types. A numerical simulation model based on the Navier–Stokes equation was employed. The effects of power take-off (PTO) damping coefficient, wave periods, and draft/displacement on the hydrodynamic performance of the two structure shapes were simulated and investigated. The results reveal that the L type performs better in shorter wave periods, and the trapezoidal type exhibits a higher CWR in intermediate wave periods. This study offers knowledge of the design and protection of the two WEC-FB types.

Keywords

Floating breakwater / Wave energy converter / Hydrodynamic performance / Capture width ratio / Transmission coefficient / CFD simulation

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