流體與結構物之間的交互作用為多領域物理問題，當結構物為一彈性體時，更增加了求解問題之難度。本研究使用之數值軟體為開源計算流體力學軟體OpenFOAM，其基於C++程式語言開發，並利用求解器solids4Foam分別求解流體與固體控制方程式並於流固交界面進行數據交換，以達成彈性體流固耦合之數值模擬。流體控制方程式使用Reynolds-Averaged Navier-Stokes並以流體體積法(VOF)建構自由液面；考慮彈性結構物之大變形因此本構關係式使用Saint Venant-Kirchhoff Law。
本研究首先以Allo et al. (2023)之實驗配置模擬二維潰壩波撞擊剛性垂直平板，並與Allo et al. (2023)實驗結果比較，驗證本數值模式模擬二維潰壩波撞擊剛性結構物交互作用之適用性。接續以Allo et al. (2023)之實驗配置模擬二維潰壩波撞擊彈性垂直平板，分析自由液面變化、速度場分布、平板受力分析以及彈性平板頂部位移量分析，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彈性結構物運動的能力。
最後進一步延伸模擬二維潰壩波撞擊不同尺寸之彈性垂直平板，比較不同尺寸，分析自由液面變化、速度場分布、壓力場分布、彈性平板受力分析以及彈性平板頂部位移量分析，發現當平板寬高比較小時，結構物之彈性效應較明顯，位移量較大，彈性結構物其位移量與寬高比成正比。根據懸臂樑理論，雖然結構物的形狀不同，但只要寬高比相同，其受力和運動行為會具有高度之相關性，而當寬高比相同之前提下，於彈性平板頂部位移量對於彈性平板高度會成正比。

Currently, research predominantly focuses on the interaction between fluids and rigid structures, with comparatively less attention given to the interaction between fluids and elastic structures. This study addresses this gap by utilizing the open-source software OpenFOAM, specifically the solids4Foam solver, to independently solve the fluid and solid governing equations. Data exchange at the fluid-structure interface allows for accurate numerical simulation of fluid-structure interactions involving elastic materials. The fluid equations are solved using Reynolds-Averaged Navier-Stokes equations, and the free surface is tracked using the Volume of Fluid (VOF) method, while the elastic structure's motion is modeled using the Saint Venant-Kirchhoff law. The numerical results are validated against experimental data from Allo et al. (2023), which involves dam-break wave interactions with both rigid and elastic plates. The study then extends its analysis by varying the dimensions of the elastic plates, exploring their effects on the free surface, velocity field, pressure field, and the forces exerted on the plates.

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