Establishment of Motion Model for Wave Capture Buoy and Research on Hydrodynamic Performance of Floating-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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Numerical Study on the Optimization of Hydrodynamic Performance of Oscillating Buoy Wave Energy Converter

Polish Maritime Research ◽

10.2478/pomr-2021-0005 ◽

2021 ◽

Vol 28 (1) ◽

pp. 48-58

Author(s):

Wenbin Lai ◽

Yonghe Xie ◽

Detang Li

Keyword(s):

Wave Energy ◽

Numerical Study ◽

Energy Conversion Efficiency ◽

Absorption Efficiency ◽

Wave Energy Converter ◽

Hydrodynamic Performance ◽

Energy Converter ◽

Physical Experiments ◽

Working Principle ◽

The Waves

Abstract The oscillating buoy wave energy converter (OBWEC) captures wave energy through the undulating movement of the buoy in the waves. In the process of capturing wave energy, the hydrodynamic performance of the buoy plays an important role. This paper designed the “Haida No. 1” OBWEC, in which the buoy adopts a form of swinging motion. In order to further improve the hydrodynamic performance of the buoy, a 2D numerical wave tank (NWT) model is established using ADINA software based on the working principle of the device. According to the motion equation of the buoy in the waves, the influence of the buoy shape, arm length, tilt angle, buoy draft, buoy width, wave height and Power Take-off (PTO) damping on the hydrodynamic performance of the buoy is studied. Finally, a series of physical experiments are performed on the device in a laboratory pool. The experimental results verify the consistency of the numerical results. The research results indicate that the energy conversion efficiency of the device can be improved by optimizing the hydrodynamic performance of the buoy. However, the absorption efficiency of a single buoy for wave energy is limited, so it is very difficult to achieve full absorption of wave energy.

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

Applied Energy ◽

10.1016/j.apenergy.2019.113996 ◽

2020 ◽

Vol 257 ◽

pp. 113996 ◽

Cited By ~ 12

Author(s):

Hengming Zhang ◽

Binzhen Zhou ◽

Christopher Vogel ◽

Richard Willden ◽

Jun Zang ◽

...

Keyword(s):

Wave Energy ◽

Wave Energy Converter ◽

Hydrodynamic Performance ◽

Energy Converter ◽

Type Wave ◽

Floating Breakwater

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Hydrodynamic performance of a dual-floater hybrid system combining a floating breakwater and an oscillating-buoy type wave energy converter

Applied Energy ◽

10.1016/j.apenergy.2019.114212 ◽

2020 ◽

Vol 259 ◽

pp. 114212 ◽

Cited By ~ 8

Author(s):

Hengming Zhang ◽

Binzhen Zhou ◽

Christopher Vogel ◽

Richard Willden ◽

Jun Zang ◽

...

Keyword(s):

Hybrid System ◽

Wave Energy ◽

Wave Energy Converter ◽

Hydrodynamic Performance ◽

Energy Converter ◽

Type Wave ◽

Floating Breakwater

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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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