Abstract
In this paper we propose a two-buoy wave energy converter composed of a heaving semi-submerged cylindrical buoy, a fixed submerged cylindrical buoy and a power take-off (PTO) system, and investigate the effect of the fixed submerged buoy on the hydrodynamics of the heaving semi-submerged buoy based on the three-dimensional potential theory. And the dynamic response of the semi-submerged buoy and the wave energy conversion efficiency of the converter are analyzed. The difference of the hydrodynamics and the wave energy conversion efficiency of a semi-submerged buoy converter with and without a fixed submerged buoy is discussed. It is revealed that the influence of the fixed submerged buoy on the exciting wave force, the added mass, the radiation damping coefficient and the wave energy conversion efficiency can be significant with a considerable variation, depending on the vertical distance between the heaving semi-submerged buoy and the fixed submerged buoy, the diameter ratio of the fixed submerged buoy to the heaving semi-submerged buoy and the water depth.
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Acknowledgement
This work was supported by the State Key Laboratory of Hydro-Science and Engineering, Tsinghua University (Grant No. 2013-KY-4).
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Project supported by the National Natural Science Foundation of China (Grant Nos. 51079072, 51279088), the National High Technology Research and Development Program of China (863 Program, Grant No. 2012AA052602).
Biography: Cen Yang (1986-), Female, Ph. D. Candidate
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Yang, C., Zhang, Yl. Numerical study of hydrodynamic behavior and conversion efficiency of a two-buoy wave energy converter. J Hydrodyn 30, 235–248 (2018). https://doi.org/10.1007/s42241-018-0025-6
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DOI: https://doi.org/10.1007/s42241-018-0025-6