Abstract
In this paper, the hydrodynamic efficiency of a floating breakwater system is experimentally studied by use of physical models. Regular waves with wide ranges of wave heights and periods are tested. The efficiency of the breakwater is presented as a function of the wave transmission, reflection, and energy dissipation coefficients. Different parameters affecting the breakwater efficiency are investigated, e.g. the number of the under connected vertical plates, the length of the mooring wire, and the wave length. It is found that, the transmission coefficient k t decreases with the increase of the relative breakwater width B/L, the number of plates n and the relative wire length l/h, while the reflection coefficient k r takes the opposite trend. Therefore, it is possible to achieve k t values smaller than 0.25 and k r values larger than 0.80 when B/L is larger than 0.25 for the case of l/h=1.5 and n=4. In addition, empirical equations used for estimating the transmission and reflection coefficients are developed by using the dimensionless analysis, regression analysis and measured data and verified by different theoretical and experimental results.
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References
Bayram, A., 2000. Experimental study of a sloping float breakwater, Ocean Eng., 27(4): 445–453.
Behzad, M. and Akbari, M., 2007. Experimental investigation on response and efficiency of moored pontoon type floating breakwaters, Iranian Journal of Science & Technology, Engineering, 31(1): 95–99.
Brebner, A. and Ofuya, A. O., 1968. Floating breakwaters, Proceedings of 11th Conference on Coastal Engineering, London, United Kingdom, 1055–1085.
Carr, J. H., 1951. Mobile breakwater, Proceeding of 2nd Conference on Coastal Engineering, Houston, Texas, 281–295.
Carver, R. D., 1979. Floating Breakwater Wave-Attenuation Tests for East Bay Marina, Olympia Harbor, Washington: Hydraulic Model Investigation, Technical Report HL79-13, U. S. Army Engineer Waterways Experiment Station, CE, Vicksburg, Mississippi.
Carver, R. D. and Davidson, D. D., 1983. Slopping floating breakwater model study, Proceeding of the Specialty Conference on Design Construction, Maintenance and Performance of Coastal Structures 83A, 417–432.
Dean, R. and Dalrymple, R. A., 1984. Wave Mechanics for Engineering and Scientists, Prentice Hall, Inc., Englewood, Cliffs, New Jersey.
Drimer, N., Agnon, Y. and Stiassnie, M., 1992. A simplified analytical model for a floating breakwater in water of finite depth, Appl. Ocean Res., 14(1): 33–41.
Dong, G. H., Zheng, Y. N., Lia, Y. C., Teng, B., Guan, C. T. and Lin, D. F., 2008. Experiments on wave transmission coefficients of floating breakwaters, Ocean Eng., 35(8–9): 931–938.
Gesraha, M. R., 1995. Hydrodynamic of Floating Pontoons Under Oblique Waves, MSc. Thesis, Irrigation and Hydraulics Department, Faculty of Engineering, Cairo University, Cairo, Egypt.
Gesraha, M. R., 2004. An eigenfunction expansion solution for extremely flexible floating pontoons in oblique waves, Appl. Ocean Res., 26(5): 171–182.
Goda, Y. and Suzuki, Y., 1976. Estimation of incident and reflected waves in random wave experiments, Proceedings of 15th Conference on Coastal Engineering, Honolulu, Hawaii, 828–845.
Fugazza, M. and Natale, L., 1988. Energy losses and floating breakwater responses, J. Waterw. Port Coast. Ocean Eng., 114(2): 191–205.
Harms, V. W., 1979. Design criteria for floating tire breakwater, J. Waterw. Port Coast. Ocean Eng., 106(2): 149–170.
Kato, J., Hagino, S., and Uekita, Y., 1966. Damping effect of floating breakwaters, J. Waterw. Harbor Div., 95(3): 1068–1078.
Kriezi, E. E., Karambas, T. V., Prinos, P. and Koutitas, C., 2001. Interaction of floating breakwaters with waves in shallow waters, International Conference IAHR, Beijing, China, 69–76.
Koraim, A. S., 2005. Suggested Model for the Protection of Shores and Marina, Ph. D. Thesis, Civil Engineering, Zagazig University, Zagazig, Egypt.
Koraim, A. S. and Rageh, O. S., 2010. Hydraulic performance of vertical walls with horizontal slots used as breakwater, Coast. Eng., 57(8): 745–756.
Koutandos, E. V., Karambas, T. V., Prinos, P. and Koutitas, C., 2004. Floating breakwater response to waves action using a Boussinesq model coupled with a 2DV elliptic solver, J. Waterw. Port Coast. Ocean Eng., 130(5): 243–255.
Koutandos, E. V., Prinos, P., and Gironella, X., 2005. Floating breakwaters under regular and irregular wave forcing: reflection and transmission characteristics, J. Hydraul. Res., 43(2): 174–188.
Liang, N. K., Huang, J. S., and Li, C. F., 2004. A study of buoy floating breakwater, Ocean Eng., 31(1): 43–60.
Lochner, R., Faber, O., and Penny, W. G., 1948. The Bombardon floating breakwater, The Civil Engineer in War 2, Docks and Harbors, The Institution of Civil Engineers, London, England.
Macagno, E. O., 1953. Fluid mechanics: experimental study of the effects of the passage of a wave beneath an obstacle, Proceedings of the Academic des Sciences, Paris, France.
Mani, J. S., 1991. Design of Y-frame floating breakwater, J. Waterw. Port Coast. Ocean Eng., 117(2): 105–119.
McCartney, B. L., 1985. Floating breakwater design, J. Waterw. Port Coast. Ocean Eng., 111(2): 304–318.
Murali, K. and Mani, J. S., 1997. Performance of cage floating breakwater, J. Waterw. Port Coast. Ocean Eng., 123(4): 172–179.
Rageh, O. S., El-Alfy, K. S., Shamaa, M. T. and Diab, R. M., 2006. An experimental study of spherical floating bodies under waves, Proc. 10th Int. Water Technol. Conf. (IWTC10), Alexandria, Egypt, 357–375.
Rageh, O. S., Koraim, A. S. and Salem, T. N., 2009. Hydrodynamic efficiency of partially immersed caissons supported on piles, Ocean Eng., 36(14): 1112–1118.
Sutko, A. A. and Haden E. L., 1974. The effect of surge, heave and pitch on the performance of a floating breakwater, Proceedings of the Floating Breakwater Conference, Newport, Rhode Island, 41–53.
Tolba, E. R., 1998. Behavior of Floating Breakwater Under Wave Action, Ph.D. Thesis, Suez Canal University, Port Said, Egypt.
Williams, K. J., 1988. An experimental study of wave obstacle interaction in a two dimensional domain, J. Hydraul. Res., 26(4): 463–482.
Williams, A. N. and McDougal, W. G., 1996. A dynamic submerged breakwater, J. Waterw. Port Coast. Ocean Eng., 122(6): 288–296.
Williams, A. N., Lee, H. S., and Huang, Z., 2000. Floating pontoon breakwaters, Ocean Eng., 27(3): 221–240.
Yamamoto, T., 1981. Moored floating breakwater response to regular and irregular waves, Appl. Ocean Res., 3(1): 27–36.
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Koraim, A.S., Rageh, O.S. Effect of under connected plates on the hydrodynamic efficiency of the floating breakwater. China Ocean Eng 28, 349–362 (2014). https://doi.org/10.1007/s13344-014-0028-1
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DOI: https://doi.org/10.1007/s13344-014-0028-1