An Experimental Study of Regular Long Crested Waves over a Crescent Type Shoal

Wen-Kai Weng ； Jaw-Guei Lin ； Chun-Sien Hsiao

《Journal of Marine Science and Technology》 21卷2期 (2013/04) Pp. 222-228

https://doi.org/10.6119/JMST-013-0313-1

並列摘要

Converting the ocean wave energy into electric power is one possibility of the development of alternative and nonpolluting sources of energy. Many researches concerning converters and their converting efficiency of wave power were developed and discussed in the last years. However, converting wave energy into electric power does not only depend upon converting system but condition of sea state essentially. A calm sea state with lower wave energy is difficult to drive converting device working and is unable to satisfy the minimum economical requirement. Unfortunately, wave heights in the sea state around Taiwan are mostly too smaller to extract the wave energy except winter and typhoon. In this study, a crescent type shoal was created for concentrating wave energy and enhancing energy density. The new submerged artificial topography is constructed as convex topography at seaside with increasing slope to the crest line and decreasing slope to the concave shape topography at landside. A series of hydraulic model tests in a wave basin about the transformations and deformations of regular long crested waves over this type shoal had been accomplished in order to evaluate its efficiency on collecting wave energy. The results show the crescent type shoal can concentrate wave energy and enlarge energy density behind the shoal, and all the experimental results indicate wave energy ratio above 8 times of the incident wave energy can be obtained for incoming wave passing through the shoal, especially for the case of wave period T = 1.5 sec this ratio reaches to 14 times.

並列關鍵字

regular waves ； crescent shoal ； wave energy

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