本文以二維數值黏性造波水槽模擬橢圓函數波通過透水與不透水系列潛堤之布拉格現象。本文使用之模式在水體區求解RANS (Reynolds Averaged Navier-Stokes Equations)方程式，在透水結構物區則求解VARANS (volume-averaged / Reynolds Averaged Navier-Stokes Equations)方程式並利用雙方程 紊流模式模擬波浪通過不透水與透水潛堤之紊流效應，並以流體體積法 (Volume of Fluid)追蹤自由液面，以期了解在橢圓函數波通過潛堤產生布拉格共振時潛堤附近之自由液面及流場狀況。
由本文數值模擬結果可知波浪通過系列潛堤之孔隙率越大，所造成的反射率會越小。此外更進一步探討比較波浪通過透水及不透水系列潛堤之流場、渦度及紊流動能之差異。

The main object of this study is to numerically investigate the Bragg-resonance interaction between cnoidal waves and submerged coastal obstacles. Both permeable and impermeable obstacles are considered.
The model named Cornell BReaking And Structure (COBRAS) calculates the mean flow fields outside and inside porous structures based on Reynolds Averaged Navier-Stokes (RANS) equations and Volume-Averaged/Reynolds Averaged Navier-Stokes (VARANS) equations, respectively. The turbulent kinematic energy (TKE) within the flow fields is estimated by performing closure model and the free surface deformations are tracked using volume of fluid method (VOF).
There are four-type submerged obstacles with different porosities and shapes (i.e. rectangular and arc) employed to study Bragg-resonance beha-viors. Our results suggest that the greater porosity the smaller reflection rate is given. Additionally, the numerical observations on TKE and fluid-vorticity due to wave-structure interaction are drawn.

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