张力腿平台的整体设计及拟静力性能分析

结合南海海域条件对传统式张力腿平台进行整体设计,计算平台所受各种环境荷载的大小,并采用拟静力分析法分析此平台的非线性运动响应,考虑平台水平漂移和下沉的非线性关系以及张力腿预张力、横截面面积、就位长度和立柱横截面面积等参数对平台运动响应的影响.     

张力腿平台在随机波浪中的耦合运动响应研究

文章研究了张力腿平台在随机波中长期海况下的耦合响应。推导了振动微分方程中的质量矩阵、耦合刚度矩阵、阻尼矩阵和运动坐标系下张力腿平台波浪外荷载。采用微元法对立柱和浮筒进行离散,运用龙格-库塔法对运动微分方程进行了数值求解。海浪谱采用Jonswap谱,随机波采用蒙特卡罗法来模拟,对不同海况下张力腿平台耦合动力响应、张力腿张力变化进行了能量谱分析。并且比较分析了不同浪向角、不同谱峰周期对平台运动响应的影响。对考虑耦合与不考虑耦合张力腿平台响应进行了比较。     

考虑风浪流的TLP张力腿张力响应规律分析

文章研究了张力腿平台在风浪流中的张力腿的张力变化规律。推导了微分方程中的质量矩阵、耦合刚度矩阵、阻尼矩阵和运动坐标系下张力腿平台波浪外荷载。采用微元法对立柱和浮筒进行离散,运用龙格—库塔法对张力腿平台耦合运动微分方程进行了数值求解。对不同海况下和不同浪向角下张力腿平台张力腿张力变化进行了能量谱分析,并在上海交通大学海洋工程国家重点试验室中通过缩尺比为1:40的模型对数值模拟的结果进行了试验验证。比较了考虑风和流以及不考虑风和流的结果。     

规则波下张力腿平台时域响应分析

讨论规则波下某张力腿平台的动力响应时域运动特性。着重分析入射波角度(15°,22.5°和45°),波高(6m,8m和10m)及波周期(10s,12s和14s)对张力腿平台各自由度运动、顶端张力的影响。探讨吃水高度、工作水深、不同张力腿数目对张力腿平台运动特性的影响。计算结果表明:由于张力腿平台各自由度对入射波角度、波高和波周期敏感度不同,张力腿平台在不同波浪参数下的运动特性(如位移幅值、平衡位置等)及顶端张力表现各异;不同吃水下的张力腿平台位移大小、平衡位置和运动方向等均不同。工作水深越大,各自由度运动越剧烈,这体现了工作环境对张力腿平台运动具有较大影响。张力腿数目越多,张力腿平台运动的位移、幅度等越小,随时间变化也越稳定。     

500 m水深张力腿平台总体运动性能分析

为了验证张力腿平台在中国南海500 m水深下的环境适应性,采用时域耦合分析的方法分析500 m水深下张力腿平台的总体运动性能,重点分析张力腿平台关键运动参数,如平台水平位移、升沉运动、气隙和筋腱张力等,基于模型试验修正的数值分析,结果表明,张力腿平台在南海500 m水深下具有良好的运动性能,可以满足作业要求。     

多因素下张力腿平台耦合动力响应特性研究

考虑立管、张力腿及平台本体的非线性耦合,建立六自由度的振动微分方程。推导了方程中的质量矩阵、耦合刚度矩阵、阻尼矩阵及波浪荷载的计算公式。采用微元法对立柱和浮筒进行离散,求得方程数值解。比较分析了四种工况下张力腿平台的耦合动力响应、张力腿及立管张力的变化,揭示了波浪周期、波高、浪向角、预张力、工作水深等多因素对张力腿平台运动响应的影响。     

平台运动影响下张力腿涡激振动特性研究（英文）

张力腿涡激振动易引起系泊系统的疲劳损伤,危害张力腿平台的安全性和可靠性。该文借鉴细长立管涡激振动的相关研究,同时考虑张力腿与立管在截面尺度、预张力大小以及边界条件存在的巨大差距,采用切片理论结合CFD数值模拟方法,对平台运动影响下张力腿涡激振动开展了研究。考虑定常张力与时变张力对涡激振动的影响,采用GAMBIT软件分区建立了多切片计算网格,将编制求解涡激振动的UDF程序嵌入Fluent软件中,采用动网格技术实现流场的更新并计算作用于张力腿上的瞬时升力和拖曳力。文中还比较了仅考虑流和考虑浪、流联合作用张力腿的时变张力影响,研究了两种典型波高共计六种工况,计算结果表明:随着流速的增加,各模态权重比例将发生跳转现象;尽管由于平台运动导致张力腿受力的随机性,但平台运动对张力腿涡激振动影响较小。     

平台运动影响下张力腿涡激振动特性研究

张力腿涡激振动易引起系泊系统的疲劳损伤,危害张力腿平台的安全性和可靠性。该文借鉴细长立管涡激振动的相关研究,同时考虑张力腿与立管在截面尺度、预张力大小以及边界条件存在的巨大差距,采用切片理论结合CFD数值模拟方法,对平台运动影响下张力腿涡激振动开展了研究。考虑定常张力与时变张力对涡激振动的影响,采用GAMBIT软件分区建立了多切片计算网格,将编制求解涡激振动的UDF程序嵌入Fluent软件中,采用动网格技术实现流场的更新并计算作用于张力腿上的瞬时升力和拖曳力。文中还比较了仅考虑流和考虑浪、流联合作用张力腿的时变张力影响,研究了两种典型波高共计六种工况,计算结果表明：随着流速的增加,各模态权重比例将发生跳转现象;尽管由于平台运动导致张力腿受力的随机性,但平台运动对张力腿涡激振动影响较小。     

畸形波作用下张力腿平台的瞬时响应

应用Tromas等(1991)提出的新波理论的概念,建立了极限入射波浪模型,并把该模型引入到极限波浪与平台互相作用的水动力计算中.研究中应用大连理工大学海岸及近海工程实验室开发的频域波浪力分析程序WAFDUT1.4,得到结构的波浪力传递函数和水动力系数.通过平台运动方程在时域内计算得到运动响应和张力腿受力.最后,进一步研究了张力腿平台的刚度系数和波浪周期的改变对张力腿平台的运动响应和张力腿受力的影响.     

张力腿平台水动力响应分析

张力腿平台作为一种典型的深水浮式平台,具有半顺应半固定的运动特征.本文以1000米水深TLP平台为例,详细叙述了TLP平台水动力分析的过程和方法,包括有限元模型的建立,水动力特征的计算,水动力荷载响应的计算以及运动响应分析.     

33rd International Conference on Ocean,Offshore and Arctic Engineering （OMAE2014）

正San Francisco,California,June 8-13,2014.OMAE 2014 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to:·meet and present advances in technology and its scientific support;·to exchange ideas and experiences whilst promoting technological progress and its application in industry·to promote international cooperation in ocean,offshore and arctic engineering.In line with the tradition of excellence of previous OMAE conferences,more than 900 technical papers are planned for presentation.Outreach for Engineers Specialty Forum This Specialty Forum is designed for students and professionals who may not be familiar with the Ocean and Offshore industry,as well as those who have just recently specialized in this field.     

The 11th International Conference on Hydrodynamics (ICHD 2014)

正19–24 October 2014 SingaporeCONFERENCE THEMES The overall aim of the ICHD Conference is to provide a forum for participants from around the world to review,discuss and present the latest developments in the broad discipline of hydrodynamics and fluid mechanics.The first International Conference on Hydrodynamics(ICHD)was initiated in 1994 in Wuxi,China.Since then,9 more ICHD conferences were held subsequently in Hong Kong,Seoul,Yokohama,Tainan,Perth,Ischia,Nantes,Shanghai and St Petersburg.Evidently the ICHD conference has become an important event among academics,researchers,engineers and operators,working in the fields closely related to the science and technology of hydrodynamics.The 11th ICHD will be held in Singapore in 2014.     

第十二届深水操作会议和展览会(英文)

正November 4-6,2014Moody Gardens HotelConvention Center/Galveston,TX The Deepwater Operations Conference and Exhibition is celebrating its 12th anniversary this year.This growing event will continue the tradition of excellence in addressing operational challenges involved in developing deepwater resources.We will return to the Moody Gardens Hotel and Convention Center on November 5-7,2014 in Galveston,Texas.     

舰艇反鱼雷技术

对目前舰艇反鱼雷技术中的非杀伤、软杀伤和硬杀伤等比较先进的手段进行了阐述,并在此基础上分析研究了舰艇反鱼雷技术的发展趋势。     

Community-Based Management for Sustainable Fisheries Resources in Phang-nga Bay,Thailand

Fishing communities, the Government of Thailand Department of Fisheries, local nongovermnental organizations, universities, the Food and Agriculture Organization of the United Nations (FAO), and FAO's Bay of Bengal Program have undertaken a partnership in management of Phang-nga Bay's coastal resources. It is the first project of its kind in Thailand, and although still in the early stages, offers insights that may contribute to our knowledge of how we can improve our management of coastal resources, including the importance of (1) building relationships within the governance process; (2) combining education, enforcement, and economic incentives to achieve compliance; (3) implementing solutions early; and (4) government support of community-based decisions. These insights reinforce trends emerging in other coastal management projects in the Asian region.     

Catalyzing Coastal Management in Kenya and Zanzibar: Building Capacity and Commitment

Site-based projects were initiated in Chawka Bay-Paje, Zanzibar, and Nyali-Bamburi-Shanzu, Kenya, to demonstrate the benefits of an integrated coastal management (ICM) approach for addressing coastal issues such as tourism development and enhancement of resource-dependent village economies in eastern Africa. A two-year, multidonor project used three primary strategies to make rapid, but sustainable, progress toward ICM. These included using interagency government teams for ICM planning, adopting an internationally recognized framework for ICM as a project ''road map,'' and explicitly incorporating capacity-building strategies into all aspects of the project. Within two years, integrated ICM action strategies, prepared through participatory processes, were being implemented at both sites, and both teams were working to expand the scale and scope of ICM in their nation. More importantly, the project helped create committed, capable, interagency groups that continue to work together to address urgent ICM issues.     

Journal of Marine Science and Application 2014 Sum. Contents

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Errata

正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.     

单相PWM整流器的建模与仿真分析

文章详细分析了单相VSR型PWM整流器的整流原理,建立了电流内环,电压外环的单相VSR型PWM整流控制器的数学模型和逻辑框图。在MATLAB／Simulink软件环境中进行了仿真,分析了模型的可行性。     

A simplified method for reliability- and integrity-based design of engineering systems and its application to offshore mooring systems

This paper presents a simplified method for the reliability- and the integrity-based optimal design of engineering systems and its application to offshore mooring systems. The design of structural systems is transitioning from the conventional methods, which are based on factors of safety, to more advanced methods, which require calculation of the failure probability of the designed system for each project. Using factors of safety to account for the uncertainties in the capacity (strength) or demands can lead to systems with different reliabilities. This is because the number and arrangement of components in each system and the correlation of their responses could be different, which could affect the system reliability. The generic factors of safety that are specified at the component level do not account for such differences. Still, using factors of safety, as a measure of system safety, is preferred by many engineers because of the simplicity in their application. The aim of this paper is to provide a simplified method for design of engineering systems that directly involves the system annual failure probability as a measure of system safety, concerning system strength limit state. In this method, using results of conventional deterministic analysis, the optimality factors for an integrity-based optimal design are used instead of generic safety factors to assure the system safety. The optimality factors, which estimate the necessary change in average component capacities, are computed especially for each component and a target system annual probability of system failure using regression models that estimate the effect of short and long term extreme events on structural response. Because in practice, it is convenient to use the return period as a measure to quantify the likelihood of extreme events, the regression model in this paper is a relationship between the component demands and the annual probability density function corresponding to every return period. This method accounts for the uncertainties in the environmental loads and structural capacities, and identifies the target mean capacity of each component for maximizing its integrity and meeting the reliability requirement. In addition, because various failure modes in a structural system can lead to different consequences (including damage costs), a method is introduced to compute optimality factors for designated failure modes. By calculating the probability of system failure, this method can be used for risk-based decision-making that considers the failure costs and consequences. The proposed method can also be used on existing structures to identify the riskiest components as part of inspection and improvement planning. The proposed method is discussed and illustrated considering offshore mooring systems. However, the method is general and applicable also to other engineering systems. In the case study of this paper, the method is first used to quantify the reliability of a mooring system, then this design is revised to meet the DNV recommended annual probability of failure and for maximizing system integrity as well as for a designated failure mode in which the anchor chains are the first components to fail in the system.