流體與結構物之間的交互作用為多物理場問題。當結構物為彈性體時，該交互作用更為複雜。本研究使用的數值模式為基於C++程式語言與有限體積法開發的開源CFD軟體OpenFOAM，透過求解器solids4Foam控制流體與固體求解器分別求解流體與固體的控制方程式並於流固交界面進行數據交換，實現彈性體的流固耦合模擬。流體的控制方程式使用Reynolds-Averaged Navier-Stokes；彈性結構物的本構關係式使用Saint Venant-Kirchhoff Law。另外，本研究引入stabilized k-ωSST紊流模式(Larsen & Fuhrman, 2018)改善紊流強度高估的問題，並引入幾何流體體積法IsoAdvector (Roenby & Jasak, 2016)進行介面重建以得到更準確的自由液面。本研究首先以Wu et al. (2012)的實驗配置模擬孤立波通過單個潛沒式垂直剛性結構物，分析自由液面演化、速度場分布、渦度場演化，以及紊流強度分布並與Wu et al. (2012)實驗結果比較，驗證本數值模式模擬孤立波與潛沒式結構物的強非線性交互作用之適用性。接著本研究進一步模擬孤立波通過單個潛沒式垂直彈性結構物，分析速度場分布、紊流強度分布，以及彈性結構物的受力、位移並與實驗結果比較，驗證本數值模式模擬兩相流與彈性體的流固耦合之適用性，以及本數值模式預測潛沒式彈性結構物運動的能力。
最後，本研究進一步延伸模擬孤立波通過間隔一定距離的雙潛沒式垂直彈性結構物，分析不同水平間距的雙潛沒式彈性結構物之彈性效應對流場的影響。

In the present study, the process of solitary wave interaction with double submerged elastic structures is simulated by an open-source software-OpenFOAM, where a fluid-structure interaction toolbox solids4Foam is employed to perform a strong coupling partitioned approach. Wave generation and absorption are performed by the wave generation toolbox waves2Foam. The incompressible fluid is described by Reynolds-Averaged Navier-Stokes equations, turbulence modeling is performed by the stabilized k-ωSST turbulence closure model, the free surface is captured by GVOF IsoAdvector, and the deformation of the elastic structure is described by Saint Venant-Kirchhoff Law. There are two experiments to validate the accuracy of the numerical model. In the first experiments, the solitary wave passing through the submerged rigid structure is considered to confirm that the numerical model is capable of simulating the strongly nonlinear interaction of a solitary wave with the submerged structure. In the other experiments, the solitary wave passing through the submerged elastic structure is considered to confirm the ability of the numerical model to simulate the water wave interaction with the elastic structure. Finally, the solitary wave interaction with the double submerged elastic structure at various distances is considered. The evolution of the free surface, velocity fields, turbulence intensity fields, displacement of the elastic structure, force acting on the elastic structure, and the coefficients of reflection and transmission are analyzed.

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