本研究利用計算流體動力學的數值方法對流體力學控制方程進行模擬，討論離岸風機基樁與規則波之間的相互作用。將平均 Navier-Stokes 方程與 RNG k-ε紊流模型相結合，以探討基樁發生溯升時的瞬態情況。有限體積法則是用進行離散解的數值模擬，採用體積分數法可求解數值波浪水槽自由液面部分空氣和水的兩相流動問題。本研究探討在使用活塞式造波機的情況下，規則波在斜坡演化的過程及其對離岸風機基樁溯升現象的影響。在波浪驗證部分，本研究首先利用國立成功大學水工試驗所大型斷面水槽的一系列規則波條件進行了數值模擬，並利用數值造波板模擬活塞式造波機的功能。數值造波板主要是以動態網格分層網格技術為基礎，作為模擬造波板與水體實際交互作用的情形。最後，本研究除了利用溯升方程式估計波浪與結構相互作用引起的垂直水位抬升外，並利用快速傅立葉變換、希爾伯特-黃變換和經驗模態分解法進行波浪在斜床演化分析。

In this study, the CFD method is used to carry out numerical simulation of the interaction between the offshore wind turbine foundation and a series of regular waves. The Reynolds Average Navier-Stokes (RANS) equation is combined with the RNG k-ε turbulence closure to explore the transient phenomena of run-ups around the monopile foundation. The finite volume law is a numerical simulation for discrete solutions. The finite volume method can be used to solve the two-phase flow of air and water on the free surface in the numerical wave tank. This study investigates the evolution of regular waves propagating over the slope and its influence on the run-up heights of offshore wind turbine foundation by using the piston-type wave generator. In order to demonstrate the accuracy of wave generation, a series of regular wave cases conducted in the super wave flume at Tainan Hydraulic Laboratory of the National Cheng Kung University were considered to perform numerical simulation. In addition, the wave-maker theory was used to simulate the real function of the piston wave-maker. The numerical wave-maker is mainly based on the dynamic layering method for simulating the actual interaction between the wave-maker and the fluids. Finally, in addition to using the run-up equation to estimate the vertical water elevation caused by the interaction of the wave and the structure, this study also uses the fast Fourier transform, Hilbert-Huang transform and empirical mode decomposition method to analyze the evolution of waves over the sloping bed.

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