臺灣博碩士論文加值系統

本研究探討波浪經過浮式柔性孔隙結構物時波浪之減衰，改變不同結構物長度及不同沒水深度，對其反射係數、透射係數及能量損失係數的影響。透過水工模型試驗的方式，在水深0.7公尺之斷面水槽進行單一方向規則波試驗。
由試驗結果分別探討反射係數KR、透射係數KT及能量損失係數KL與相對水深、相對沒水深度及結構物相對長度之比較。由試驗結果可發現，反射係數K_R約在結構物相對長度b/L為0.8左右時，有最低值。能量損失係數KL在結構物相對長度b/L小於0.8時，能量損失係數KL隨著結構物相對長度增加而上升，結構物相對長度b/L大於0.8時，能量損失係數KL趨於平穩；在相對沒水深度d/L小於0.05時，能量損失係數隨著相對沒水深度上升而增加，相對沒水深度d/L大於0.05時，能量損失係數趨於平穩。

This study investigates the wave attenuation on the wave passing through a floating poro-flexible structure. Effects of the lengths of structure and the depths of under water on the reflection coefficient KR, transmission coefficient KT and energy loss coefficient KL ard studies. The hydraulic model test was carried out in a water tank with a water depth of 0.7 meter and a single direction regular wave.
Base on the experimental results, the reflection coefficient KR, the transmission coefficient KT and the energy loss coefficient KL are compared with the relative water depth, the relative depth of under water and the relative length of structure respectively. The experimental results show that the reflection coefficient KR has the lowest value when the relative length of structure b/L is about 0.8. When the relative length of structure b/L is smaller than 0.8, the energy loss coefficient KL increases with the increase of the relative length. When the relative length of structure b/L is bigger than 0.8, the energy loss coefficient KL tends to be stable. When the relative depth of under water d/L is smaller than 0.05, the energy loss coefficient KL increases with the relative depth of under water, and the energy loss coefficient KL tends to be stable when the relative depth of under water d/L is bigger than 0.05.

摘要 I
Abstract II
目次 III
圖目錄 V
表目錄 V
照片目錄 VIII
第一章 緒論 1
1-1 研究動機及目的 1
1-2 前人研究 1
1-3 研究與內容 2
1-4 本文組織 2
第二章 模型配置與試驗方法 3
2-1 試驗設備 3
2-1-1 中斷面造波水槽 3
2-1-2 造波機 4
2-1-3 波高計與增幅器 5
2-1-4 資料擷取系統與軟體 6
2-2 模型製作與試驗配置 8
2-2-1 試驗儀器設置 8
2-2-2 浮式結構模型之製作與擺置 8
2-3 浮式結構物基本參數率定 13
2-3-1孔隙率(n’)之率定 13
2-3-2 抗壓強度及彈性係數之率定 14
2-3-3 滲透係數kp及紊流阻力係數Cf之率定 16
2-4 試驗條件 23
2-4-1 試驗波浪條件 23
2-4-2 試驗浮式結構物型式 23
2-5 試驗步驟 26
2-5-1 試驗流程 26
2-5-2 波高計率定 26
2-5-3 空水槽率定 27
2-6 試驗資料分析 28
2-7 因次分析 31
第三章 結果分析與討論 33
3-1 自由運動下相同沒水深度，不同結構物長度之比較 33
3-1-1沒水深度d=0.112公尺(d/h=0.16) 33
3-1-2沒水深度d=0.158公尺(d/h=0.226) 36
3-1-3沒水深度d=0.350公尺(d/h=0.5) 39
3-2 自由運動下相同結構物長度，不同沒水深度之比較 42
3-2-1結構物長度b=1.9公尺(b/h=2.71) 42
3-2-2 結構物長度b=3.8公尺(b/h=5.42) 45
3-3自由運動下之綜合比較 48
3-3-1 反射係數KR比較 48
3-3-2 透射係數KT比較 50
3-3-3 能量損失係數KL比較 52
3-4自由運動浮體與固定浮體中心之比較 54
3-4-1 沒水深度d=0.112公尺(d/h=0.16) 54
3-4-2 沒水深度d=0.158公尺(d/h=0.226) 57
3-4-3 沒水深度d=0.350公尺(d/h=0.5) 60
3-4-4 固定浮體中心下，結構物長度b=3.8公尺(b/h=5.42) 63
第四章 結論與建議 66
4-1 結論 66
4-2 建議 66
參考文獻 68

1. Black, J.L., Mei, C.C., & Bray, M.C.G. 1971. “Radiation and scattering of water waves by rigid bodies,” Journal of Fluid Mechanics, 46(1), pp. 151-164. doi:10.1017/S0022112071000454
2. Chen, K., Wiegel, R.L., 1970. “Floating breakwaters for reservoir marinas,” Proceedings of the 12th Coastal Engineering Conference, Washington, DC, vol. III, pp. 1647-1666.
3. Dong, G.H., Zheng, Y.N., Li, Y.C., Teng, B., Guan, C.T., Lin, D.F., 2008. “Experiments on wave transmission coefficients of floating breakwaters,” Ocean Engineering, 35, pp. 931-938.
4. Gesraha, M.R., 2006. “Analysis of π shaped floating breakwater in oblique waves: I. Impervious rigid wave boards,” Applied Ocean Research, 28, pp.327-338.
5. Goda. Y., and Suzuki. Y., 1976. “Estimation of incident and reflected waves in random wave experiments,” Proceedings of 15th International Conference in Coastal Engineering, Hawaii, ASCE, pp. 828-845.
6. Hsiao, S.S., Fang, H.M., Chang, C.M., Lee, T.S., 2008. “Experimental study of the wave energy dissipation due to the porous-plied structure,” Proceedings of Eighteenth (2008) International Offshore and Polar Engineering Conference, Canada, vol. 3, pp. 592-598.
7. Hegde, A.V., Kamath, K., Deepak, J.C., 2008. “Mooring forces in horizontal interlaced moored floating pipe breakwater with three layers,” Ocean Engineering, 35, pp. 165-173.
8. Keller, J. B. 1948. “The solitary wave and periodic waves in shallow water,” Comm. Pure Appl. Math., 1, pp.323-339. doi:10.1002/cpa.3160010402
9. Lan, Y.-J. 2018. “Study on wave attenuation induced by the effect of offshore flexible vegetation,” Proceedings of the 40th Ocean Engineering Conference in Taiwan, Kaohsiung, Taiwan, pp. 197-202.
10. Lan, Y.-J. 2019. “An analysis solution for wave propagating through a fixed and floating poroelastic medium,” Proceeding of the 29th Internation Ocean and Polar Engineering Conference, Honolulu, Hawaii, USA, pp. 3764-3680.
11. Littman, W. 1957. “On the existence of periodic waves near critical speed,” Comm. Pure Appl. Math., 10, pp. 241-269. doi:10.1002/cpa.3160100203
12. McCartney, B.L., 1985. “Floating breakwater design,” Journal of Waterway Port, Coastal, and Ocean Engineering, ASCE, 111(2), pp. 304-318.
13. Mei, C.C., & Black, J.K. 1969. “Scattering of surface waves by rectangular obstacles in waters of finite depth,” Journal of Fluid Mechanics, 38(3), pp. 499-511. doi:10.1017/S0022112069000309
14. Murali, K., Mani, J.S., 1997. “Performance of cage floating breakwater,” Journal of Waterway, Port, Coastal, and Ocean Engineering, ASCE, 123(4), pp. 172-179.
15. Sannasiraj, S.A., Sundar, V., Sundaravadivelu, R., 1998. “Mooring forces and motion response of pontoon-type floating breakwaters,” Ocean Engineering, 25(1), pp. 27-48.
16. Sollitt, C.K. and Cross, R.H. 1972. “Wave transmission through permeable breakwaters,” Proc. 13th Coastal Engineering Conf., ASCE, Vancouver, pp.1827-1846.
17. Stiassnie, M., Drimer, N., 2003. “On a freely floating porous box in shallow water waves,” Applied Ocean Research, 25, pp. 263-268.
18. 陳柏嘉2000.“張力式多孔介質浮堤在波流場中的交互作用”，國立中山大學海洋環境及工程學系碩士論文。
19. CNS中國國家標準檢測方法，國家標準(CNS)網路服務系統，http://www.cnsonline.com.tw/.