|
|
Characteristics of dynamic pressure on floating V-shaped breakwater |
Ding Ning1,2, Yu Jianxing1, Hou Jiajia1,3 |
1.State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China; 2.Institute of Military Transportation, Tianjin 300161, China; 3.Tianjin Xingang Shipbuilding Heavy Industry Co. Ltd., Tianjin 300456, China |
|
|
Abstract In order to determine the wave force(or moment)in design and structure analysis of floa-ting V-shaped breakwater, the dynamic pressure distribution and its amplitude on the wet surface of breakwater was calculated and analyzed in a regular wave. Considering the diffraction effect, the velo-city potential around the breakwater was calculated based on the 3D linear potential flow theory in frequency domain by using boundary element method and 3D Green functions, which were solved by both integral method and eigenfunction expansion approach. The dynamic pressure was calculated by using the linear Bernoulli equation according to the velocity potential just obtained numerically. Moreover, the dynamic pressure and its amplitude on the wet surface were estimated in a regular wave. The results of an example indicate that the dynamic pressure distribution on the wet surface is sinusoidal longitudinally and attenuating downward vertically. The distance between the two nearest peaks of dyna-mic pressure is approximately equal to the quotient of incident wave length divided by the cosine of the angle between the incident wave direction and the breakwater. Besides, the maximums of dynamic pressure(about 2 kPa)are on the free surface, while the minimums(about 0.2 kPa)are in the bo-ttom of breakwater, thus the dynamic pressure near free surface plays a very important part in wave force(or moment)of floating V-shaped breakwater.
|
Received: 24 January 2013
|
|
|
|
[1]Wang Huanyu, Sun Zhaochen. Experimental study on the influence of geometrical configuration of porous floa-ting breakwater on performance[J]. Journal of Marine Science and Technology, 2010,18(4):574-579.[2]Yoon J, Cho Y S. Experimental research on effective floating breakwaters[J]. Journal of Coastal Research, 2011(SI 64): 631-635.[3]Tadayon M H, Bargi K, Sharifian H, et al. Effect of geometric dimensions on the transmission coefficient of floa-ting breakwaters[J]. International Journal of Civil and Structural Engineering, 2010,1(4): 775-781.[4]Pena E. Structural behavior of floating breakwaters with different mooring lines. Application to marina coruna[C]//Proceedings of the 9th International Conference on Coasts, Ports and Marine Structures, 2010.[5]程建生, 缪国平, 尤云祥, 等. 波浪在V形贯底式防波堤上绕射的解析研究[J]. 上海交通大学学报, 2005, 39(5): 813-817. Cheng Jiansheng, Miao Guoping, You Yunxiang, et al. Analytical research on the wave diffraction on V-type bottom-mounted breakwaters[J]. Journal of Shanghai Jiaotong University, 2005, 39(5): 813-817.(in Chinese)[6]陆志妹,缪国平,朱仁传,等. V形贯底式防波堤上波浪作用力的解析研究[J]. 水动力学研究与进展: A辑, 2007, 22(1):135-141. Lu Zhimei, Miao guoping, Zhu Renchuan, et al. Analytical research on the wave force exerted on V-shaped bottom-mounted breakwaters[J]. Journal of Hydrodynamics: Ser A, 2007,22(1): 135-141.(in Chinese)[7]Chang Kao-Hao, Tsaur Deng-How, Huang Liang-Hsiung. Accurate solution to diffraction around a modified V-shaped breakwater[J]. Coastal Engineering, 2012,68:56-66.[8]丁宁, 王广东, 贺辰, 等. V形浮式防波堤几何参数对消波效果的影响研究[J]. 军事交通学院学报, 2010, 12(1): 77-80. Ding Ning, Wang Guangdong, He Chen, et al. Geometry parameters′ influence on wave eliminating effect of V-shape floating breakwater[J]. Journal of Academy of Military Transportation, 2010, 12(1):77-80.(in Chinese)[9]Martinelli L, Ruol P, Zanuttigh B. Impulsive loads on interconnected floating bodies[C]//Proceedings of the 28th International Conference on Ocean, Offshore and Arctic Engineering, 2009:1131-1138.[10]Elchahal G, Younes R, Lafon P. Parametrical and motion analysis of a moored rectangular floating breakwater[J]. Journal of Offshore Mechanics and Arctic Engineering, 2009,131(3):1-11.[11]戴遗山. 舰船在波浪中运动的频域与时域势流理论[M]. 北京: 国防工业出版社, 1998: 125-133.[12]Newman J N. Algorithms for the free-surface green function[J]. Journal of Engineering Mathematics, 1985,19(1):57-67.[13]Michael J B. Analytical and numerical models of the RIBSXM99 ocean-scale prototype[R]. Washington, DC: US Army Corps of Engineers, 2001. |
|
|
|