一艘运营散货船主机减振分析评估

针对一艘散货船主机振动过大的问题,在实船测试和计算分析的基础上,提出减振方案,对减振方案进化量化评估,评估和方案实施后的实船测试验证表明,达到了预期的减振效果,解决了同批船舶主机振动问题。     

船用柴油机燃油管系减振研究

为解决某船用柴油机燃油管系低压管路振动强烈问题,实船测量了燃油管路和主机振动、燃油脉冲压力和管路固有频率,确定喷油泵柱塞间隙性进、回油诱导管路内燃油压力脉动是激励管路振动的主要原因。从结构和流体两个角度分析了管系减振的方法,通过加焊马脚改变管系的刚度和加装阻尼器降低燃油脉冲强度两种方法来降低管路的振动。试验结果表明,两种方法皆有效地降低了管路的振动,特别是阻尼器从源头降低燃油脉冲能量的减振效果更明显。     

船用二冲程柴油机缸体上部振动信号的特征分析

对船用二冲程低速柴油主机液压排气阀壳、喷油器顶部、缸盖表面和燃油泵表面的振动信号进行了测试与分析,介绍了测试系统的组成和振动测点布置,进行了振动信号的时域波形分析,证实了利用排气阀壳表面的振动信号可以监测液压排气阀的开启和关闭时刻,比缸盖和缸套表面的振动信号更敏感。确定了喷油器顶部的振动信号与燃油喷射有很强的对应性,可以用来监测二冲程柴油机的燃油喷射定时,为船用低速柴油主机的状态监测和故障诊断提供了一个实用的监测方法。     

某V型高速柴油机振动测试及动力学分析

针对某艇主机12缸V型高速柴油机振动过大的问题,开展柴油机动力学分析与振动测试,得到各主要工况下的振动响应。研究结果表明,柴油机振动干扰成分丰富,且分布在很宽的频域上,主要干扰频率为基频的0.5阶、1.0阶及3.0阶,设计时应重点考虑隔振系统刚度与主要干扰阶次的关系。对主机振动过大的原因进行分析,结果表明引起共振的干扰频率、存在激励力或结构局部共振、柴油机结构轻量化及刚性较低是主要影响因素,对柴油机减振设计具有指导意义。     

主机燃油回油管频繁漏油故障分析及处理

针对某船主机燃油回油管频繁发生漏油事故,经过分析得出燃油脉冲震荡和主机振动是回油管振动的直接原因,共振是造成其漏油的主要原因,进而提出改变回油管固有振动频率、降低启阀压力等处理措施。     

某V型高速柴油机振动测试及动力学分析

针对某艇主机12缸V型高速柴油机振动过大的问题,开展柴油机动力学分析与振动测试,得到各主要工况下的振动响应。研究结果表明,柴油机振动干扰成分丰富,且分布在很宽的频域上,主要干扰频率为基频的0.5阶、1.0阶及3.0阶,设计时应重点考虑隔振系统刚度与主要干扰阶次的关系。对主机振动过大的原因进行分析,结果表明引起共振的干扰频率、存在激励力或结构局部共振、柴油机结构轻量化及刚性较低是主要影响因素,对柴油机减振设计具有指导意义。     

减振腔冲击特性的试验研究

某舰载核探测设备在爆破冲击作用下,易造成核心探测器件的破坏和失效,由此设计了减振腔结构以实现缓冲和减振.采用电动振动测试系统产生的半正弦冲击波,对减振腔进行了多组冲击载荷试验,获得了减振腔在输入系列冲击振动载荷下系统输入 - 输出特性的数据,通过分析计算得到了系统的减振比.结果表明,减振腔系统具有良好的抗冲隔振性能.     

低振动噪声环形永磁侧推装置在综合型测量船上的应用

基于常规侧推装置所采用的减振降噪措施,对其在测量船上的适用性进行了相关研究,通过与新型环形永磁侧推优异的静音特性进行对比和论证后,得出环形永磁侧推更适用于综合型测量船低振动噪声设计要求的结论.     

主机弹性支撑安装技术研究

新型航天测量船作为典型的高科技船,为适应航天测控工作环境和乘员舒适性要求,其主机选用了带弹性减振块的弹性支撑安装技术。本文主要介绍了该弹性支撑安装技术的要点及解决方案。     

SEC船用主机功率—燃油测量仪性能分析及其在NOx实船测试中的应用

日本SHOYON公司生产的“SEC船用主机性能监测系统”主要包括主机功率－燃油测量仪和主机燃烧性能监测仪两部分,可以实时监测船舶主机的推进性能和燃烧性能。现详细介绍SEC主机功率－燃油测量仪的系统组成,测量原理,主要功能,实际操作要点以及在NOx实船测试中的应用等内容。     

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

正~~     

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;     

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。     

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）.     

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.     

桥梁防撞设施物理模型试验

物理模型试验是预报防撞设施所受撞击力及优化设计方案的主要方法之一。结合杭州湾大桥柔性防撞设施及东海大桥独立式防撞体设计方案,阐述了船—防撞体撞击试验的基本原理、方法、试验方案及相关试验结果。提出了柔性防撞系统的优化方案。试验结果表明,该方案经济有效,可供预报类似桥梁防撞设施撞击力时参考。     

印尼某电厂码头水工建筑物设计

印尼某电厂项目码头水工建筑物包括码头、防波堤和护岸等主要组成部分。在该项目水工建筑物的设计过程中,综合考虑当地的自然条件、施工能力和材料来源等因素,不断优化结构选型和结构断面。根据不同使用要求,护岸分别采用直立式和斜坡式2种结构型式,推荐的设计方案节省投资、施工方便,可供同类工程设计参考。     

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.     

开放式数据挖掘系统模型

目前国内已经出现了少量的数据挖掘相关产品。国内数据挖掘软件无论从数量还是质量上比较，都与国外软件存在着较大的差距。随着数据仓库技术的普及，数据挖掘应用的需求越来越强烈，如何缩短这种差距，研发数据挖掘软件产品成为国内业界的一个重要问题。通过引用目前国际通用数据挖掘标准技术来构建开放式的数据挖掘系统模型，该系统模型从可扩展性、可重用性、易用性等方面得到了加强。