Hydrodynamic performance of a floating breakwater as an oscillating-buoy type wave energy converter

Abstract Floating-type wave energy converter has the advantages of high wave energy conversion efficiency, strong shock resistance ability in rough sea and stable output power. So it is regarded as a promising energy utilization facility. The research on hydrodynamic performance of wave capture buoys is the precondition and key to the wave energy device design and optimization. A simplified motion model of the buoys in the waves is established. Based on linear wave theory, the equations of motion of buoys are derived according to Newton’s second law. The factors of wave and buoys structural parameters on wave energy absorption efficiency are discussed in the China’s Bohai Sea with short wave period and small wave height. The results show that the main factor which affects the dynamic responses of wave capture buoys is the proximity of the natural frequency of buoys to the wave period. And the incoming wave power takes a backseat role to it at constant wave height. The buoys structural parameters such as length, radius and immersed depth, influence the wave energy absorption efficiency, which play significant factors in device design. The effectiveness of this model is validated by the sea tests with small-sized wave energy devices. The establishment methods of motion model and analysis results are expected to be helpful for designing and manufacturing of floating-type wave energy converter.

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Nonlinear Time-Domain Simulation of the Heaving-Buoy Type Wave Energy Converter by Using Three-Dimensional Potential Numerical Wave Tank Under Irregular Wave Conditions

Volume 9: Ocean Renewable Energy ◽

10.1115/omae2020-18392 ◽

2020 ◽

Author(s):

Sung-Jae Kim ◽

Weoncheol Koo ◽

Moo-Hyun Kim

Keyword(s):

Wave Energy ◽

Time Domain ◽

Three Dimensional ◽

Wave Energy Converter ◽

Hydrodynamic Performance ◽

Numerical Wave Tank ◽

Energy Converter ◽

Wave Tank ◽

Type Wave ◽

Numerical Wave

Abstract The aim of this paper is to evaluate the hydrodynamic performance of a heaving buoy type wave energy converter (WEC) and power take-off (PTO) system. To simulate the nonlinear behavior of the WEC with PTO system, a three-dimensional potential numerical wave tank (PNWT) was developed. The PNWT is a numerical analysis tool that can accurately reproduce experiments in physical wave tanks. The developed time-domain PNWT utilized the previously developed NWT technique and newly adopted the side wall damping area. The PNWT is based on boundary element method with constant panels. The mixed Eulerian-Lagrangian method (MEL) and acceleration potential approach were adopted to simulate the nonlinear behaviors of free-surface nodes associated with body motions. The PM spectrum as an irregular incident wave condition was applied to the input boundary. A floating or fixed type WEC structure was placed in the center of the computational domain. A hydraulic PTO system composed of a hydraulic cylinder, hydraulic motor and generator was modeled with approximate Coulomb damping force and applied to the WEC system. Using the integrated numerical model of the WEC with PTO system, nonlinear interaction of irregular waves, the WEC structure, and the PTO system were simulated in the time domain. The optimal hydraulic pressure of the PTO condition was predicted. The hydrodynamic performance of the WEC was evaluated by comparing the linear and nonlinear analytical results and highlighted the importance accounting for nonlinear free surfaces.

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Study on Performance of Savonius Rotor Type Wave Energy Converter Used in Conjunction with Floating Breakwater

China Ocean Engineering ◽

10.1007/s13344-021-0052-x ◽

2021 ◽

Vol 35 (4) ◽

pp. 578-587

Author(s):

Zuo-shi Liu ◽

Kai Gong ◽

Fang-ping Huang ◽

Yan-chen Huang

Keyword(s):

Wave Energy ◽

Wave Energy Converter ◽

Energy Converter ◽

Savonius Rotor ◽

Type Wave ◽

Floating Breakwater ◽

Rotor Type

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Experimental investigation on the hydrodynamic performance of a wave energy converter

China Ocean Engineering ◽

10.1007/s13344-017-0058-6 ◽

2017 ◽

Vol 31 (3) ◽

pp. 370-377 ◽

Cited By ~ 4

Author(s):

Xiong-bo Zheng ◽

Yong Ma ◽

Liang Zhang ◽

Jin Jiang ◽

Heng-xu Liu

Keyword(s):

Experimental Investigation ◽

Wave Energy ◽

Wave Energy Converter ◽

Hydrodynamic Performance ◽

Energy Converter

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A Study on Development of the Performance Analysis Method of the Floating OWC-WEC Using the MPS Method

Volume 6: Ocean Space Utilization ◽

10.1115/omae2015-42049 ◽

2015 ◽

Cited By ~ 1

Author(s):

Yutaro Sasahara ◽

Mitsuhiro Masuda ◽

Kiyokazu Minami

Keyword(s):

Wave Energy ◽

Two Phase Flow ◽

Wave Energy Converter ◽

Response Analysis ◽

Phase Flow ◽

Energy Converter ◽

Wave Impact ◽

Two Phase ◽

Mps Method ◽

Type Wave

When concrete examination towards utilization is needed, it is necessary to estimate the safety and the performance of a floating Oscillation Water Column (OWC)-type wave energy converter under abnormal oceanographic phenomenon such as large waves, wave impact force, deck wetness and complex motion of mooring system. Therefore, to choose a proper numerical method is important. This present paper describes a fundamental study about estimation of safety and performance of floating OWC-type wave energy converter using the two-phase flow MPS method. In this research, firstly, new algorithm is installed in order to solve problems of the two-phase flow MPS method. Secondly, applicability to an response analysis of a wharf installation type OWC-WEC of the improved MPS method is examined by wave pressure acting to the OWC-WEC and response in the air chamber of the OWC-WEC.

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