小水线面双体船耐波性预报

采用Choung M.Lee改进的切片理论及其公式,编制小水线面双体船耐波性预报软件.该软件可用于在各种波向角时,对不同航速小水线面双体船匀速航行中的运动响应进行预报,包括在规则波或不规则波中的垂荡、纵摇、横荡、横摇、首摇幅值预报,以及其它耐波性统计特性预报.利用本预报软件对某型试验船的耐波性能进行了计算,并与试验结果进行了比较分析,计算结果符合小水线面双体船的耐波性规律.本预报方法可为小水线面双体船的船型设计和稳定鳍选择提供耐波性方面的理论依据.     

小水线面双体船耐波性预报

采用Choung M．Lee改进的切片理论及其公式，编制小水线面双体船耐波性预报软件。该软件可用于在各种波向角时，对不同航速小水线面双体船匀速航行中的运动响应进行预报，包括在规则波或不规则波中的垂荡、纵摇、横荡、横摇、首摇幅值预报，以及其它耐波性统计特性预报。利用本预报软件对某型试验船的耐波性能进行了计算，并与试验结果进行了比较分析，计算结果符合小水线面双体船的耐波性规律。本预报方法可为小水线面双体船的船型设计和稳定鳍选择提供耐波性方面的理论依据。     

小水线面双体船支柱斜度对其耐波性能影响分析

基于三维势流理论,本文研究了不同支柱倾斜角度的小水线面双体船在设计航速下的耐波性能。将规则波中的运动响应幅值函数与海浪谱结合得到运动统计有义值。对比不同支柱倾斜角度的频率响应曲线,发现在相同海况条件下随着支柱倾斜角度增加,垂荡和纵摇峰值降低。结果表明,通过倾斜支柱可增加船舶运动的附加质量和阻尼,削弱频率响应曲线共振峰。     

小水线面双体船支柱斜度对其耐波性能影响分析

基于三维势流理论,本文研究了不同支柱倾斜角度的小水线面双体船在设计航速下的耐波性能。将规则波中的运动响应幅值函数与海浪谱结合得到运动统计有义值。对比不同支柱倾斜角度的频率响应曲线,发现在相同海况条件下随着支柱倾斜角度增加,垂荡和纵摇峰值降低。结果表明,通过倾斜支柱可增加船舶运动的附加质量和阻尼,削弱频率响应曲线共振峰。     

不同航速下某浅吃水船耐波性分析

采用Hydro Star软件，系统分析某浅吃水船在不同航速时的耐波性能。研究结果表明：零航速、设计吃水工况下，横浪时垂荡和横摇运动最为显著。随着波浪偏移至艏/艉附近（±30°），横摇响应幅值算子（RAO）迅速减小；对于左舷处的监测点，纵向、垂向加速度RAO曲线关于左右舷浪向呈不对称分布，差异在横浪附近表现得尤为明显，横向运动的对称性则与此无关；横浪下1阶波浪力矩表现为双峰构型，相较于斜浪更大，导致横摇运动加剧；而斜浪下，低频波浪力矩对横摇起主要作用，且更高的航速对应了更大的等效黏性阻尼，从而一定程度上抑制了横摇响应；根据4级海况的短期预报结果，垂向加速度沿船长不同位置分布不均，随浪向、航速的变化规律也各不相同，在实际营运中应予以综合考虑，以避免不利因素的影响。     

小水线面双体船斜浪中运动的参数激振初探

船舶经常会在斜浪中航行,特别是在海峡内航行。此时,船舶运动是一种纵摇,横摇和垂荡的藕合运动,这种藕合运动容易导致参数共振,使船舶的耐波性变坏。以中国科学院科学考察船"实验1"号的一艘实船和代号T-SWDTH的一个船舶设计方案为例,计算分析了它们在斜浪中航行时的船体运动和参数共振问题,证明小水线面双体船在斜浪中横摇不会造成垂荡和纵摇的参数共振。     

迎浪规则波中小水线面双体船纵向运动及波浪载荷非线性特性数值分析

基于RANS方程和VOF模型求解船体粘性兴波流场,开展了小水线面双体船(Small Waterplane Area Twin Hulls,SWATH)迎浪规则波中纵向运动及波浪载荷的非线性特性研究.通过数值计算结果与模型试验结果的对比分析,验证了文中方法的有效性;在此基础上,较为系统地分析了SWATH船的垂荡及纵摇运动响应、垂向加速度和波浪载荷的一阶及二阶量随入射波高的变化规律,指出SWATH船的运动响应及载荷与波高存在非线性的关系,尤其体现在响应共振区附近;相比于船体垂荡和纵摇运动,垂向加速度及波浪载荷的非线性特性更为显著.     

三体船主体尺度对其在波浪中动态响应的研究

基于有限元方法,通过仿真计算,比较了三种不同主体尺度下三体船的垂荡、纵摇、横摇运动响应算子。因不同的航行速度对运动算子有一定影响,故分别在低航速和高航速下进行比较。通过不同航速下的垂荡、纵摇、横摇性能对比,得出主体狭长型三体船运动响应性能均最佳,最适合作为三体船主体的尺度。     

迎浪规则波中小水线面双体船纵向运动及波浪载荷非线性特性数值分析（英文）

基于RANS方程和VOF模型求解船体粘性兴波流场,开展了小水线面双体船(Small Waterplane Area Twin Hulls,SWATH)迎浪规则波中纵向运动及波浪载荷的非线性特性研究。通过数值计算结果与模型试验结果的对比分析,验证了文中方法的有效性;在此基础上,较为系统地分析了SWATH船的垂荡及纵摇运动响应、垂向加速度和波浪载荷的一阶及二阶量随入射波高的变化规律,指出SWATH船的运动响应及载荷与波高存在非线性的关系,尤其体现在响应共振区附近;相比于船体垂荡和纵摇运动,垂向加速度及波浪载荷的非线性特性更为显著。     

双体工程辅助船波浪载荷

为预报双体工程辅助船在波浪中的运动响应,采用直接计算法和SESAM软件对其波浪载荷进行直接计算。计算结果表明:双体工程辅助船的垂荡运动响应在横浪时达到最大;纵摇运动响应从横浪到顶浪逐渐增大;横摇运动响应在横浪时达到最大;纵摇有关扭矩在艏(艉)斜浪时达到最大,满载出港工况下的响应幅值最大,压载到港和满载出港结冰工况下的响应幅值比较接近;纵向扭矩在艏斜浪附近时响应幅值达到最大,压载到港工况下的响应幅值最大,满载出港结冰工况下的响应幅值最小,即双体工程辅助船在压载航行时的纵向扭转较为严重。从双体工程辅助船结构设计、驾驶及其理论研究等角度提出了建议与对策。     

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.     

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.     

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.     

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.     

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。     

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.     

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.     

含裂纹钢板复合材料修补强度和刚度数值分析

用ANSYS有限元分析软件对复合材料补片修复含边裂纹和中心裂纹钢板的强度和刚度进行了数值分析.引入相对刚度的概念,研究了钻有止裂孔裂纹的长度对损伤钢板相对刚度的影响,分析了损伤钢板刚度复合材料贴片修补效果;引入屈服载荷提高率的概念,分析了损伤钢板强度的修复效果.     

混凝土道路、堆场面层裂缝的产生与防治

从混凝土道路、堆场的各个结构层分析裂缝产生的原因,并针对性地说明预防措施,阐述裂缝维修方法。     

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。