彈性透水潛堤與波浪間的交互作用，過去的研究少有針對彈性透水潛堤附近之流場特性進行探討。本文利用波高計量測水位變化，分析透過率與反射率，並嘗試應用質點影像測速 (Particle Image Velocimetry，PIV)量測波浪通過單一彈性透水潛堤之流場特性。針對PIV所量測到之速度場進行平均速度、渦流、流線、水平速度剖面、渦心軌跡與最大渦流渦度值等特性分析。
本研究首先量測波浪通過柔軟且具滲透性的潛堤模型時波浪的反射與透過率。由試驗結果和線性波理論及前人解析解進行比較，得到透水彈性潛堤之波浪透過率小於不透水潛堤情形，波浪反射率則因潛堤彈性運動對波浪產生造波作用，使得試驗量測得到之反射率有大於不透水剛性潛堤的情形，顯示了潛堤彈性效應對於波浪變化的影響，本文分析結果與Lan (2001) 所提出之理論解析解做比較，有良好的一致性。
PIV量測主要針對兩組規則波波浪條件及三種不同材質特性之潛堤進行量測與分析，比較剛性不透水、彈性不透水及彈性透水潛堤之量測結果。得到彈性不透水潛堤在彈性運動之作用下，上游側順時針渦度值小於剛性不透水潛堤，而下游側逆時針渦度值大於剛性不透水潛堤之情形。彈性透水潛堤具有滲透性，因此在上游側不易產生順時針渦流。由於潛堤堤頂表面的摩擦力，在堤頂產生順時針渦流，而下游側因為潛堤透水的效應，逆時針渦流能夠有較長時間的發展，加上彈性運動之作用下，逆時針渦流渦度值較大。

Effects of the interaction between waves and porous elastic submerged breakwaters are well investigated in numerical studies (Lan and Lee, 2010 ; Lan et al.,2011), but much less is known about the flow field of waves propagating over a single submerged porous elastic breakwater experimentally. The objective of the present study is to investigate the wave reflection and transmission using wave gauges, and characteristics of flow field obtained by PIV. The mean velocity and vorticity were calculated from ensemble averaging 30 instantaneous velocity fields.
The PIV measurements were performed in two wave conditions and three breakwaters with different meterials. The experiments results were compared with rigid and impermeable case, elastic and impermeable case and elastic and permeable case. Measurements of wave reflection and transmission induced by soft and permeable submerged breakwater are both carried out. The results shows that wave transmission for porous elastic case is smaller than that of rigid and impermeable case. The oscillatory motion of porous elastic submerged breakwater can produce extra reflective waves and result in larger reflection rate. Furthemore, the experimental result is in good agreements with numerical analysis (Lan, 2000).
Positive and negative vortices are generated due to corner separation. The negative vortex obtained in elastic and permeable breakwater is generated by the surface friction at the top of the structure. Because of the permeability, it is found that the negative vortex at seaward side for elastic and permeable case is smaller than that of rigid and impermeable case. On the contrary, the positive vortex at leeward side for elastic and permeable case is larger than the other two cases.

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