基于有限元模型深海潜航器观察窗受力分析

大深度载人潜航器观察窗作为驾驶员观察周围环境的窗口,其受力情况复杂,直接影响整机的安全性,针对其受力情况进行分析。在传统理论分析方法的基础上,提出适用于锥台形观察窗位移、应力分析的方法,建立相应的位移和应力的理论分析模型,对2种边界条件下的位移和应力进行分析;利用有限元分析软件,对比理论计算和有限元分析结果,分析无网格和有网格2种方法的差异与优劣;建立观察窗位移试验台,对主、侧观察窗的轴向位移开展试验研究,并对试验结果进行分析拟合,最后将试验拟合结果与理论计算和有限元分析结果进行对比。对观察窗的Fatigue Life进行分析,分析的疲劳寿命结果代入Miner理论公式中,计算大观察窗和小观察窗的疲劳损伤情况。结果表明:理论计算结果可以较好地反应观察窗上的位移分布,有限元分析结果偏大;主观察窗的使用寿命为26 432 Circle,侧观察窗的使用寿命为21 359 Circle。     

基于有限元模型深海潜航器观察窗受力分析

大深度载人潜航器观察窗作为驾驶员观察周围环境的窗口,其受力情况复杂,直接影响整机的安全性,针对其受力情况进行分析.在传统理论分析方法的基础上,提出适用于锥台形观察窗位移、应力分析的方法,建立相应的位移和应力的理论分析模型,对2种边界条件下的位移和应力进行分析;利用有限元分析软件,对比理论计算和有限元分析结果,分析无网格和有网格2种方法的差异与优劣;建立观察窗位移试验台,对主、侧观察窗的轴向位移开展试验研究,并对试验结果进行分析拟合,最后将试验拟合结果与理论计算和有限元分析结果进行对比.对观察窗的Fatigue Life进行分析,分析的疲劳寿命结果代入Miner理论公式中,计算大观察窗和小观察窗的疲劳损伤情况.结果表明:理论计算结果可以较好地反应观察窗上的位移分布,有限元分析结果偏大;主观察窗的使用寿命为26432 Circle,侧观察窗的使用寿命为21359 Circle.     

焊接结构多轴疲劳寿命预测结构应力法

海洋工程焊接结构形式复杂且遭受随机波浪载荷作用,焊接接头多数处于多轴疲劳状态,而目前工程上主要采用基于单轴疲劳理论和试验的方法预测结构的疲劳寿命。为了提高焊接结构疲劳寿命预测的准确性,文章提出了一种评估焊接接头疲劳强度的新型结构应力法,并与临界面理论相结合,能够用于实际焊接结构的多轴疲劳寿命预测。通过对国际上已公开发表的疲劳试验数据进行有限元分析,证明了文中提出的结构应力法比传统的热点应力法具有更高的精度,以及该方法应用于焊接结构多轴疲劳寿命预测的可行性。最后,应用该方法对一个T型管节点进行了多轴疲劳寿命计算。     

船舶结构疲劳控制设计数据库的研究

如何在设计阶段就能够预测结构的疲劳寿命一直以来是个工程上的难题。因此,科学地预测结构疲劳寿命具有较大的现实意义。针对该问题,本文基于工程热力学基本理论、结构焊接数值算法、结构可靠性、结构疲劳寿命等理论建立了结构疲劳寿命评估计算模型。以为基础,借助有限元法对结构疲劳寿命进行计算,并建立了船舶结构疲劳设计数据库。该数据库能够对结构疲劳寿命进行有效地预测,具有一定的工程应用价值。     

考虑焊接残余应力释放的结构疲劳寿命分析方法研究

焊接残余应力对于焊接结构的疲劳寿命产生很显著的影响,同时循环载荷作用下焊接残余应力会出现释放现象,因此有必要对焊接件疲劳寿命预测方法进行研究.基于改进的McEvily疲劳裂纹扩展速率模型,同时结合课题组研究得到的AH36钢对接焊平板残余应力释放计算公式,提出考虑焊接残余应力释放的结构物疲劳寿命计算方法.随后,以潜艇锥柱耐压壳的疲劳为例,详细阐述了本文提出的疲劳寿命分析方法的计算流程.考虑耐压壳焊接顺序影响,分析了含半椭圆表面裂纹的锥柱耐压壳疲劳寿命.对比文献的试验结果,表明焊接结构疲劳寿命计算公式有较好的预测效果,可以用于评估带表面裂纹焊接件在拉伸循环载荷作用下的疲劳寿命.     

AH32钢T型焊接接头疲劳强度的试验与数值模拟

对AH32钢T型试件进行疲劳试验,并利用有限元软件对T型焊接接头的应力分布及疲劳寿命进行数值模拟,最终将疲劳试验结果与数值模拟结果对比分析。研究发现,T型焊接接头在焊趾附近处应力值最大,寿命最短。本文研究结果为今后船海结构物的疲劳寿命预测提供了有益参考。     

弧形管疲劳寿命预测研究

弧形管是一种常用的管路连接件,在服役时长期受到大位移疲劳载荷的作用。传统工程实践中针对挠性接管处于疲劳载荷在可靠性检验多采用抽样试验方法,该方法存在试验成本高,置信度差的缺点,且未从失效机理上对弧形管疲劳失效进行有效分析。本文将汽车行业橡胶件疲劳寿命预测常用的裂纹萌生法应用于弧形管。通过单轴疲劳拉伸试验,建立基于各种疲劳损伤参数的寿命预测模型,结合弧形管三维实体有限元仿真模型和寿命预测模型,对拉压工况下的疲劳寿命进行预测并通过加速试验进行了验证。该论文研究结果可用于指导弧形管疲劳可靠性设计。     

舰船燃气涡轮叶片三维热流固耦合应力应变分析及寿命预测

为提高燃气轮机的可靠性、可用性以及可维护性而进行的寿命预估与减损控制研究,需要对燃气轮机的关键零部件进行结构特性分析。对舰船燃气轮机涡轮叶片在紧急升工况载荷谱下的应力应变状态进行了三维热流固耦合有限元分析,针对典型载荷谱计算了涡轮叶片应力应变的变化规律,对涡轮叶片材料进行了控制应变试验,为叶片寿命预测提供了必要的参数。根据应力应变分析结果利用Basquin公式和Manson-Coffin公式计算了2个危险点处的疲劳裂纹起始寿命。并根据分析结果对涡轮叶片进行了寿命预测,预测结果可以作为燃气轮机使用维修的参考依据。     

岸边集装箱起重机金属结构疲劳寿命研究

以岸边集装箱起重机为研究对象，研究在产品设计阶段对金属结构疲劳寿命进行预测的基本计算方法，并编制计算程序，对结构在一定工作条件下的疲劳寿命进行计算分析。     

基于总应变能的多轴疲劳模型研究

该研究提出一种多轴疲劳寿命预测模型。结合现有的几种多轴疲劳模型的优点和不足之处,分别对正应变能部分和剪应变能部分做出了修正,提出了一个能够适用于多种载荷形式的多轴疲劳寿命预测模型。该模型通过求解莫尔圆把剪应变幅作为临界面判定参量,把临界面上的总应变能作为损伤参量。运用SNCM630合金钢、纯钛和钛合金等4种材料的疲劳试验数据对提出的模型进行评估和验证,尽管材料特性和载荷形式各异,但所有的预测寿命基本都落在了试验寿命两倍的公差带以内,这证明提出的新模型具有较高的预测精度。     

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.     

Journal of Marine Science and Application 2014 Sum. Contents

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第34届海洋、离岸及极地工程国际会议(英文)

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;     

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.     

Recent progress on wave induced loading measurements in warships

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.     

联合作战计划和执行系统

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。     

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.     

Eastbound or westbound ?

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）.     

Impact of regulation on the performances of long-distance transport services: A comparison of the different approaches in Sweden and Norway

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.