Analytical Study on Transmission and Reflection of Non-Linear Shallow Water Waves     

Miao Guoping Liu Yingzhong Professor  Dept. of Naval Architecture  Ocean Engineering  Shanghai Jiao Tong University  Shanghai 《中国海洋工程》1991,(1)

The analytical study is made by using the method of matched asymptotic expansions on the transmission and reflection of solitary waves and cnoidal waves on two-dimensional floating bodies. The solutions give explicitly the variation pattern of the transmitted waves and the characteristics of the reflected waves, including the wave profile, amplitude, phase shift and evolution. The effects of the gap between the body and the sea bottom on the transmission and reflection of those waves are also discussed.  相似文献   

大型海藻对富营养化海水养殖区生物修复的研究与展望   总被引：23，自引：4，他引：23  

杨宇峰  费修绠 《中国海洋大学学报(自然科学版)》2003,33(1):53-57

当前 ,中国的多数海水养殖区富营养化相当严重。富营养化可引发赤潮和养殖动物病害 ,给养殖业带来巨大损失。海带、龙须菜、条斑紫菜等大型海藻 ,生产力很高 ,在生长过程中可大量吸收 C,N,P等生源要素 ,在水生态系统碳循环和减缓富营养化方面有很重要的作用。此外 ,海藻产品可食用、作为饲料、工业原料和有机肥料 ,是具有较高价值的商品。大规模栽培大型海藻是减轻养殖区富营养化的有效途径之一。  相似文献   

Transient Hydroelastic Response of VLFS by FEM with Impedance Boundary Conditions in Time Domain   总被引：1，自引：1，他引：1  

邱流潮  刘桦 《中国海洋工程》2005,19(1):1-9

A time-dependent finite element method (FEM) is developed to analyze the transient hydroelastie responses of very large floating structures (VLFS) subjected to dynamic loads. The hydrodynamic problem is formulated based on the linear theory of fluid and the structural response is analyzed based on the thin plate theory. The FEM truncates the unbounded fluid domain by introducing an artificial boundary surface, thus defining a finite computational domain. At this boundary surface an impedance boundary conditions are applied so that no wave reflections occur. In the proposed scheme, all of the procedures are processed directly in time domain, which is efficient for nonlinear analyses of structure floating on unbounded fluid. Numerical results indicate acceptable accuracy of the proposed method.  相似文献   

Experimental Study on Rectangular Floating Breakwaters     

Yao Guoquan Ma Zhixiong Ding Bingcan Prof. Senior Engineer  River  Harbour Department  Nanjing Hydraulic Research Institute  Nanjing Senior Engineer  River  Harbour Department  Nanjing Hydraulic Research Institute  Nanjing Engineer  River  Harbour Department  Nanjing Hydraulic Research Institute  Nanjing 《中国海洋工程》1993,(3)

This paper proposes ten types of improved floating breakwaters for experiment with regular waves, based on the experience in the development and manufacture of existing floating breakwaters both at home and abroad, and on the results of experimental studies on the hydraulic characteristics of several types of floating breakwaters. The wave heights before and behind the breakwaters are measured, the movements of floating breakwaters are observed and the chain forces of the floating breakwaters are measured. The paper studies and compares the hydraulic characteristics of the improved rectangular floating breakwaters of which the internal and external structures and their installation methods are changed. Finally the optimal type of structure is selected through experiments.  相似文献   

Investigation of Internal Turret Mooring System for Oil Production Storage Vessels     

Ma Zhiliang  Huang Xianglu  Ma Peisun Fan Genfa  Yu Xiangsan  Jin Dexian Professor  Shanghai Jiao Tong University  Shanghai Associate Professor  Shanghai Jiao Tong University  Shanghai Research Fellow  Shanghai Jiao Tong University  Shanghai 《中国海洋工程》1991,(4)

  相似文献   

New Method for Predicting the Motion Responses of A Flexible Joint Multi-Body Floating System to Irregular Waves   总被引：4，自引：0，他引：4  

CHEN  Xujun 《中国海洋工程》2001,(4):491-498

A new hybrid method of frequency domain and time domain is developed in this paper to predict the motion responses of a flexibly joint multi-body floating system to irregular waves. The main idea of the method is that the three-dimensional frequency method is used to obtain the hydrodynamic coefficients and the response equations are solved in time domain step by step. All the forces can be obtained at the same time. The motions and nonlinear mooring forces of a box type six-body floating system are predicted. A comparison of the theoretical method-based solutions with experimental results has shown good agreement.  相似文献   

海水工厂化养鱼排污水处理的实验研究与工程设计   总被引：4，自引：0，他引：4  

徐宾锋  杜守思  朱杰  林旭升  陈志成 《海洋湖沼通报》2001,(3):70-77

本文从保护海洋环境出发，论述研究设计海水工厂化养鱼排污水处理工程的重要性，提出用光合细菌（PSB）和海藻试验研究工厂化养鱼排污水处理的效率、特性及副产品的综合利用。通过工程计算，设计出工艺流程图及光合细菌反应池、二沉池和海藻塘的工程容量。  相似文献   

圆形网箱框架用PE管材的弯曲疲劳试验   总被引：1，自引：0，他引：1  

关长涛  陆光炯  林德芳  杨长厚  徐斌  黄滨 《中国海洋大学学报(自然科学版)》2006,36(2):236-240

网箱框架在风、浪、流单一载荷或其复合载荷的作用下,始终处于动态变化中,在这样的工况条件下,很容易发生疲劳破坏。本文通过对网箱框架工况条件的分析,认为网箱框架在沿直径方向的弯曲疲劳为主要因素,且在弯曲过程中周长保持不变。以圆形框架在直径方向产生20%的压缩变形为极端条件,通过几点假设,将工况条件向试验条件进行转化,提出1种圆形网箱框架用PE管材的弯曲疲劳试验方法。采用此方法对3种改性配方的聚乙烯管材样品进行了弯曲疲劳试验。结果表明,经10万次弯曲试验,3种配方的试样表面均无开裂等破坏现象,各配方的最大应力水平分别下降了14.3%,9.4%和16.9%。  相似文献   

Hiding and feeding in floating seaweed: Floating seaweed clumps as possible refuges or feeding grounds for fishes     

Sofie Vandendriessche  Marlies Messiaen  Sarah O'Flynn  Magda Vincx  Steven Degraer 《Estuarine, Coastal and Shelf Science》2007,71(3-4):691-703

Floating seaweed is considered to be an important habitat for juvenile fishes due to the provision of food, shelter, a visual orientation point and passive transport. The importance of the presence of the highly dynamical seaweed clumps from the North Sea to juvenile neustonic fishes was investigated by analysing both neuston samples (without seaweed) and seaweed samples concerning fish community structure, and length-frequency distributions and feeding habits of five associated fish species. While the neustonic fish community was mainly seasonally structured, the seaweed-associated fish community was more complex: the response of the associated fish species to environmental variables was species specific and probably influenced by species interactions, resulting in a large multivariate distance between the samples dominated by Chelon labrosus and the samples dominated by Cyclopterus lumpus, Trachurus trachurus and Ciliata mustela. The results of the stomach analysis confirmed that C. lumpus is a weedpatch specialist that has a close spatial affinity with the seaweed and feeds intensively on the seaweed-associated invertebrate fauna. Similarly, C. mustela juveniles also fed on the seaweed fauna, but in a more opportunistic way. The shape of the size-frequency distribution suggested enhanced growth when associated with floating seaweed. Chelon labrosus and T. trachurus juveniles were generally large in seaweed samples, but large individuals were also encountered in the neuston. The proportion of associated invertebrate fauna in their diet was of minor importance, compared to the proportions in C. lumpus. Individuals of Syngnathus rostellatus mainly fed on planktonic invertebrates but had a discontinuous size-frequency distribution, suggesting that some of the syngnathids were carried with the seaweed upon detachment and stayed associated. Floating seaweeds can therefore be regarded as ephemeral habitats shared between several fish species (mainly juveniles) that use them for different reasons and with varying intensity.  相似文献   

Hydroelastic Response Analysis of Mat-Like VLFS over A Plane Slope in Head Seas   总被引：2，自引：0，他引：2  

孙辉  崔维成  刘应中  廖世俊 《中国海洋工程》2003,17(3)

1 .IntroductionIntheexploitationofoceanresourcesandintheutilizationofoceanspaces,verylargefloatingstructures (VLFS)suchasMega FloatinJapan (Isobe ,1 999)andMobileOffshoreBase (MOB)inUSA (Remmers ,1 999)playasignificantrole .However,owingtotheirlargesizesandrelativelylowbendingrigidities ,theirhydroelasticresponsesinwavesareofthemostconcern .ManystudieshavebeencarriedoutforthepredictionofthehydroelasticresponsesofVLFS′s (Kashiwagi,2 0 0 0 ;Cui,2 0 0 2 ) .However,inalmostallofthesestu…  相似文献