本文以數值模式求解二維非穩態雷諾平均方程式 (RANS)及紊流模式(k-ε model)，模擬波浪入射至曲面海堤 (curved seawall) 後之流場特性。本文應用質點等位函數法 (Particle Level Set Method) 來計算波浪在溯升過程中自由液面的複雜變化。為使卡氏座標下滿足曲面海堤之不規則邊界條件，本文採用質量守恆邊界法 (Mass-Conserved Boundary Method) 模擬波浪與曲面海堤之交互作用。為了確定數值模式的準確度，本文利用前人研究來驗證本模式計算結果，包含缺口圓盤問題 (Zalesak’s problem)、均勻流通過圓柱與孤立波於斜坡上之溯升(Lin et al., 1999)，數值結果對比於實驗結果皆相當一致。在驗證數值模式之準確性後，本文首先研究曲面海堤中 Flaring Shaped Seawall (FSS) 的波壓之驗證，以Sundar and Anand (2010) Cn波入射至FSS之實驗數據，與數值結果相較吻合。後以孤立波入射至不同形狀之曲面海堤，針對其流場演變、壓力及底床剪應力以及邊界層流速等流場性質做探討。

In this study, numerical schemes are developed for simulating the fluid flow behavior near curved seawalls. The unsteady, two-dimensional Reynolds Averaged Navier-Stokes equations (RANS) and the turbulence model (k-ε model) are solved to model the real fluid behavior. A Level Set Method is adopted to capture the complex free surface evolution. A Mass-Conserved Boundary Method (MCBM) is applied to represent the fluid-solid interaction in the vicinity of curved seawalls under the Cartesian grid system. To validate the present numerical model, several numerical tests are conducted; including the Zalesak’s problem, a uniform flow past a circular cylinder, and run-up of solitary waves on a sloping bed (Lin et al., 1999). The present numerical results are in good agreement with the exact solution and experimental data. Besides, the numerical model is applied to simulate the run-up of Cnoidal waves on the Flaring Shaped Seawall (FSS). The numerical results of wave pressure on the curved seawall are compared with the experimental data (Sundar and Anand, 2010) to demonstrate the accuracy of the present model. Finally, the developed model is used to investigate the run-up of a solitary wave on different seawalls, involving the vertical wall, flaring shaped seawall, reverse flaring shaped seawall, and semicircle seawall. The free surface evolution, the flow fields, the wave pressure, the bed shear stress and boundary layer flows are discussed.

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