An investigation into wave focusing induced by the crescent shoal of different geometric parameters using the mild-slope equation

• Main Authors: Wu, Sheng-Yang, 吳聲陽
• Other Authors: Weng, Wen-Kai
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/9z39tj

碩士 === 國立臺灣海洋大學 === 河海工程學系 === 107 === The wave propagation module of the TELEMAC-MASCARET system has been applied to investigate wave focusing induced by the crescent shoal of different geometric parameters. The wave propagation toward the crescent shoal has been simulated by the mild-slope equation model ARTEMIS. In this study, the crescent shoal is composed by three elliptical equation with three adjustable parameters. The first one is the length of semi-long axis of outer edge ellipse, the second one is the length of semi-short axis of inner ellipse, and the final one is the length of semi-short axis of ellipse by elevation. From the computational results we have found, when the length of the crescent shoal is longer, the maximum dimensionless wave height is higher, while the dimensionless wave height is above 1.6 the area is smaller. Thus, the dimensionless energy density of this area is higher, which means the better wave focusing characteristics. In contrast, the maximum dimensionless wave height is reduced when the length of the crescent shoal is smaller. The dimensionless energy density of this area is lesser while the dimensionless wave height is above 1.6, resulted in poor wave focusing characteristics. As the ratio for the length of the crescent shoal to water depth, l/h = 1, there is no wave focusing characteristics.