流體與結構物之交互作用屬於一多領域物理問題，又稱為FSI問題，當結構物為一彈性體時，更增加了該問題之難度。本研究採用分區法求解流固耦合問題，分別求解流場、結構物，再透過流固交界面耦合兩求解器，流體採用之控制方程式為Navier-Stokes方程式，並以流體體積法(VOF)獲得自由液面；考慮結構物之大變形因此採用StVenant-Kirchhoff本構關係式。
所使用之數值軟體為OpenFOAM，該軟體基於有限體積架構，並採用C++語言編成。使用之求解器為solids4Foam，該求解器融合OpenFOAM流場與固體求解器，因此能處理更廣泛的流固耦合問題。
本研究首先透過孤立波流經剛性浸沒式平板以測試本模式之造波、吸波能力，分析自由液面、速度場、渦流強度以及紊流強度，與前人比較後獲得不錯的結果，此外藉由潰壩波衝擊彈性平板模擬，以確認本模式求解彈性體運動之能力。
最後進一步延伸模擬孤立波通過彈性浸沒式平板，比較不同尺寸，分析自由液面、渦度場之變化，發現當平板寬高比較小時，結構物之彈性效應較容易呈現，而由於孤立波經過平板時，彈性平板變形方向與孤立波行徑方向一致，因此相對速度較低，而細長外觀平板由於容易變形，因此消波能力較差，故自由液面下降幅度較少。

Numerous studies focus on the interaction between fluid and rigid structure for a long time but the fluid interaction with flexible structure also attract much attention. In present study, the process of water wave interaction with submerged elastic plate is simulated by an open-source software—OpenFOAM, where a wave generation toolbox waves2Foam is employed to generate and absorb wave. The incompressible fluid is described by Navier-Stokes equation, the motion of elastic body is modeled by StVenant-Kirchhoff constitutive law and the free surface elevation is tracked using VOF method. There are two experiments to validate the numerical model. In the first one the solitary wave pass through the submerged rigid plate is considered to check the ability of wave generation and absorption. The other is a dam-break flow impacting on an elastic plate. Finally, considering the solitary wave interaction with submerged elastic plate, and analyze the evolution of free surface, velocity fields and the coefficients of reflection and transmission.

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