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理论与试验研究表明,单体复合船型可以大幅提升舰船耐波性但对其静水阻力影响不大.如何准确预报该船型的运动性能一直是人们关心的问题.文中采用STF法预报深V船型与深V单体复合船型的纵向运动,研究表明,由于传统切片法基于势流理论,无法反映出复合船型组合附体的粘性效应,因此预报结果与试验结果有很大偏差.文中提出采用考虑枯性的CFD软件Fluent计算带有组合附体部分船体剖面的水动力系数,采用RANS方法计算组合附体的升力系数,同时考虑高速时船体航行姿态的影响进行修正.结果表明文中采用的预报方法可以有效提高单体复合船型运动预报精度. 相似文献
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基于势流理论的源汇分布法适合计算双体船,小水线面船等特殊形状的剖面,对常规船型的计算精度满足工程精度要求,但对粘性效应较明显的非常规船型计算精度较差。文章借助计及粘性效应的CFD软件Fluent,模拟物体在水池中作受迫振荡,采用RANS方法计算复杂形状船体剖面的简谐振荡力,对该力的拟合分解可以得到水动力系数。通过对首部形状较复杂的船型纵向运动预报结果比较表明采用RANS方法计算剖面水动力系数由于考虑了粘性效应,对阻尼系数计算更符合实际物理特征。因此对粘性影响较大的复杂船型文中提出的方法优于常规势流算法。 相似文献
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水动力系数是船舶耐波性能预报、操纵性能预报,滑行艇在静水中的运动稳定性及海豚运动预报的重要参数.探讨高效、稳定的水动力系数预报方法对准确预报上述问题具有重要的意义.该研究将地震波领域的多重透射公式应用于简单格林函数二维半理论,探讨了远方边界条件,用四阶龙阁库塔法处理自由面条件,进行详细的多重透射阶数、横剖面数、附加因子、自由面网格数量以及计算域的大小对计算结果的影响的探讨,并以Wigley船型为例计算了静水航行并做强迫振荡时的水动力系数.数值计算结果与切片方法、二维半理论复杂格林函数方法、三维频域方法及和试验结果进行了比较,比较表明多重透射公式能够有效地模拟二维半远方辐射条件,提高计算效率和稳定性,对二维半理论简单格林函数方法是一种有效的改进. 相似文献
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CFD动态网格技术在水下航行体非定常操纵运动预报中的应用研究 总被引:2,自引:0,他引:2
针对水下低速航行体非定常操纵运动中雷诺数及水动力系数随时间变化这一特点,文章采用基于动态网格技术的CFD数值方法对其进行运动模拟.通过对传统动态混合网格模型进行发展,提出了一种改进的动态混合网格模型,以此建立了非定常操纵运动数值预报方法.为验证所建立的数值预报方法对水下低速航行体操纵运动水动力的预报精度,并以带攻角均匀直航的滑行状态为研究对象,应用动网格技术对一典型水下低速航行体缩比模型主体及带附体的水动力进行了计算,结果与风洞模型试验结果吻合较好;文中进而将其应用于一水下滑翔机自航模非定常运动的预报,结果与试验符合较好,初步验证了动网格技术的应用能力和所建立的预报方法的有效性.文中的工作可以为水下航行体及其自航模非定常操纵运动的数值模拟提供基础. 相似文献
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《船舶与海洋工程学报》2014,(1):126-126
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. 相似文献
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《船舶与海洋工程学报》2014,(2)
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. 相似文献
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《船舶与海洋工程学报》2014,(4)
正St.John's,Newfoundland,Canada,May 31-June 5,2015 OMAE2015 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; 相似文献
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Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form. 相似文献
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联合作战计划和执行系统 总被引:2,自引:1,他引:1
全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划:时间不限的精密预案计划生成作战计划、方案计划或职能计划;时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础,加速应付危机的能力。 相似文献
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《船舶与海洋工程学报》2014,(1)
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. 相似文献
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《船舶与海洋工程学报》2014,(2)
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. 相似文献
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In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama?
The answer is China South Port Group (Hong Kong, Shenzhen and Guangzhou). 相似文献
The answer is China South Port Group (Hong Kong, Shenzhen and Guangzhou). 相似文献
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Gunnar Alexandersson Staffan Hultén Frode Longva 《Research in Transportation Economics》2010,29(1):212-218
Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues. 相似文献