4800标准箱集装箱船燃油闭式溢流系统设计研究

主要对燃油闭式溢流系统的组成、特点进行分析，并以4800标准箱（TEU）集装箱船为例，设计其燃油闭式溢流系统，并对其进行阻力计算，为以后相似系统设计提供计算参考。     

空气溢流系统设计

文章描述了空气溢流系统的基本概念和其常规设计,并对GL所提出的闭式燃油溢流系统及其相关的阻力计算进行了分析。     

闭式燃油溢流系统的设计

本文主要介绍了闭式燃油溢流系统的组成,三种不同的型式,设计和设备仪表的配置要求,以及系统的优点,并举例说明。     

燃油储存舱闭式溢流透气系统优化设计

针对燃油储存舱透气到主甲板上产生的油气污染问题,根据燃油储存舱闭式溢流透气系统的特点,制定优化设计方案,提出系统设计流程.以2200 TEU集装箱船为例,通过理论计算与CFD模拟仿真相结合的方式论证了优化设计方案满足系统设计要求,避免发生主甲板面油气污染的现象.     

邮轮燃油舱结构试验压头选取方法及应用

为了解决邮轮部分燃油舱及溢流舱在进行结构试验时,理论试验压头高于舱室设计压头高度的问题;基于邮轮燃油舱溢流和透气系统的特点分析按规范要求的选取方法存在的不足;提出并论证改进后的选油舱结构试验压头选取方法,首制极地探险邮轮燃油舱结构试验证明,当燃油舱及溢流舱的透气管高度超过舱室设计压头高度时,应当以油舱实际的溢流高度作为试验压头高度。     

中小型船用柴油机燃油系统的设计与管理

中小型船用柴油机燃油系统由燃油舱、燃油驳运泵、燃油注入管、日用燃油柜、日用燃油柜透气管、喷油器、喷油泵、燃油输送泵、燃油滤器、溢流管等组成。     

燃油溢流系统设计探讨

对船舶燃油溢流系统的组成和任务作简要介绍，并对燃油贮油舱的压力产生原因及防止油舱过压采取措施进行分析，同时以带流量计和溢流阀的两种燃溢流系统为例，对它们进行布置设计和压力计算。     

某船燃油辅助驳运系统改进与自控设计

针对某船燃油辅助驳运系统终端设备附属油柜容量小、驳运油泵需手动频繁起停、过驳油存在串油与跑油风险等问题,分析该燃油驳运系统泵浦扬程及流量,以及管路沿程阻力、溢流管沿程阻力等特性,提出系统改进方案与自动控制设计。     

PC2-5柴油机喷油器故障分析与修复

存在的问题:某舰PC2-5柴油机多次频繁出现主机冷却水系统故障.PC2-5柴油机的冷却水分为海水系统和闭式淡水系统,闭式淡水系统又可分为主机冷却水回路和喷油器回路两个独立系统.两个淡水冷却水系统故障,特别是喷油器喷嘴与本体之间平面常发生燃油泄漏于冷却水之中,严重影响喷油器散热冷却,经常烧坏.     

燃油及其溢流舱优化设计和结构试验

为改进国际船级社协会制定的水密舱室试验程序中有关结构试验的方法,优化现行规范中有关燃油舱结构强度的计算公式,以1974年《国际海上人命安全公约》及其修正案和船级社规范为依据,结合船上燃油及其溢流舱的典型布置,就改进燃油溢流舱的试验方法和试验压头的选取进行充分论证;对现行规范中适用于燃油舱结构强度的计算公式进行分析,指出公式中参数选取的不合理之处,并提出优化建议;通过计算分析对比发现,合理选取结构试验的压头高度和使用经优化的结构强度计算公式不仅能降低船厂对溢流舱结构试验的时间和成本,而且可使仅需满足类似适应性要求的燃油舱结构构件的设计尺寸更小、更合理。合理选取结构试验压头高度和优化规范结构强度计算公式不仅能控制生产成本、减轻空船重量、提高船舶能效,而且可为试验程序和船级社规范的修改提供技术支持,具有潜在的经济和社会效益。     

船舶在狭水道中运用GPS、ARPA、ECDIS定位技术研究

船舶在狭水道或进出港航道航行时,为确保船舶航行在预定的航迹线上,传统的定位与导航方法大多是利用助航标志。本文基于GPS、船用雷达(ARPA)和电子海图(ECDIS)等航海仪器与设备功能特点,就船舶运用GPS、船用雷达和电子海图以确定船舶在狭水道航行的航迹线方法作了研究,并就方法的运用提出了相应的注意事项。     

Humpback Whales in Tonga: An Economic Resource for Tourism

The growth of whale-watching internationally has been spectacular. It now occurs in almost 100 countries and is estimated to be worth in excess of U.S.$1 billion each year in revenue. Thus, whales have become valuable as a resource for tourism. The Vava'u island group in the northern part of the Kingdom of Tonga in the South Pacific is an area with a growing reputation as a whale-watching destination. However, the industry is relatively new there and the impacts of whale-based tourism in these islands is, as yet, unknown. In addition, there has been a recent consideration of a return to hunting whales in Tonga. As a result, concerns regarding the value of these animals for tourism and the potential impact of a return to hunting have arisen. Consequently, a study was designed to provide a preliminary assessment of the economic impacts of these animals for the island community. This study estimates that humpback whales may be worth in excess of U.S.$700,000 annually as a tourism attraction and that there is significant potential for future growth. Furthermore, the study shows that current visitors are opposed to any resumption of whaling practices in the islands and that such a move would likely displace large numbers of tourists from Tonga. Thus, it is concluded that a resumption of whaling in Tonga would likely have a significant opportunity cost in terms of lost tourism revenues.     

Effect of microbubbles on the structure of turbulence in a turbulent boundary layer

The time-averaged velocity and turbulence intensity distributions were measured by a laser Doppler velocimeter in a turbulent boundary layer filled with microbubbles. The void fraction distribution was also measured using a fiber-optic probe. The velocity decreased in the region below 100 wall units with an increase in bubble density. This led to a decrease in the velocity gradient at the wall, which was consistent with a decrease in shearing stress on the wall. The turbulence intensity in the buffer layer increased at a low microbubble density, and then began to decrease with an increasing microbubble density. Based on the present measurements, the mechanism of turbulence reduction by microbubbles is discussed and a model is proposed. Received for publication on Dec. 3, 1999; accepted on April 18, 2000     

Maneuvering simulations of pusher-barge systems

Pusher-barge systems were studied in nine different configurations. Captive model tests were performed at the Hiroshima University Towing Tank and the hydrodynamic derivatives for the various configurations were obtained. At a service speed of 7 knots, pusher-barge systems with the same number of barges but arranged in a row (shorter length overall but with a larger breadth) require more power to operate than those that were arranged in a line. When the length overall increased, the tactical diameter, advance, and transfer distances also increased, mainly due to the significant increase in the moment of inertia when barges are arranged in a line, rather than in a row. All pusher-barge systems had small first and second overshoot angles. Pusher-barge systems with the same number of barges had a longer response time to the rudder angle of attack and required a longer stopping distance when arranged in a line, mainly due to the increased moment of inertia and reduced resistance when barges are arranged in this way.     

A study of liabilities of multimodal transport operators in China

This article studies the liabilities of a multimodal transport operator under Chinese law. The present legal framework governing the multimodal transport consists of a complex array of laws and regulations. As a consequence, the applicable liability rules, the degree and the extent of the liability of a multimodal transport operator may vary from case to case. In addition, the ratification of the Rotterdam Rules would only contribute to clarification of legal complexities in a multimodal transport case where a sea leg is included. We conclude that there is a need to have a Chinese multimodal transport law which is broad enough in scope to govern the rights and liabilities of all parties involved in multimodal carriage in China.     

尾涡/固体边界交互作用下表面压力的数值模拟

当强劲的尾涡撞击到结构时,其表面压力将呈现大幅的变化.这种大幅变化的脉动压力是引起结构震动以及水动力噪声的主要原因之一.许多相关的工程领域都希望使用相对经济的方法对此压力脉动进行有效地预报.本文介绍一种已经嵌入一面元法程序(PROPELLA)的尾涡砰击模型,及其在一吊舱桨尾涡撞击支柱诱导表面压力模拟中的应用.由模拟的时均表面压力分布和相均压力的时序变化与对应的实验数据的比较来看,数值模拟与试验结果吻合较好.     

三体船型PCC风荷载的实验性研究(英文)

In recent years, demands for car transportation by a ship have been increasing with favorable economic conditions in auto sector, and the need of a pure car carrier (PCC) has grown quickly. A PCC needs huge parking space but smaller displacement since a car is comparatively light for its volume. As a result, almost all PCCs have wide breadth, shallow draft and huge structure above the water surface. These features cause some technical issues of a PCC, like lack of stability, effect of strong winds on its resistance, difficulty of course keeping in rough seas, difficulty of berthing in strong winds, and so on. To overcome these technical issues, one of the authors has proposed a new concept for a PCC. This is a trimaran PCC which has very limited transverse bulkheads in the center hull by using two side hulls as fenders. In the present research, wind forces acting on a scale model of the trimaran PCC were measured in the towing tank with a wind generator at Osaka Prefecture University. Furthermore, in order to clarify the characteristics of wind pressure on the trimaran, height and width of tunnels which are between a main hull and side hulls were changed. And then, in order to imitate a real ship, we used wind reduction technology of corner-cut design for accommodation house of the ship. Moreover, the wind pressure acting on the trimaran was compared with that on a mono-hull PCC. Using these experimental and theoretical results, an estimation method of wind pressure acting on the trimaran PCC is deduced.     

超长冷弯钢板桩的沉桩理论分析与工程实践

为解决超长冷弯钢板桩沉桩困难、易扭曲变形等问题,在理论分析的基础上推导了自重作用下细长桩的最大稳定直立长度计算公式和桩体可承受的激振力公式,为超长钢板桩的施工工艺选择提供理论依据,并在某修船坞围堰工程冷弯钢板桩施工中得到验证。解决了冷弯钢板桩易变形扭曲沉桩困难等问题,提高了工作效率。     

Locomotion by mechanical pectoral fins

The objectives of this study were the development of a new device for maneuvering an underwater vehicle using the mechanism of a fish swimming, an experimental and theoretical analysis of the hydrodynamic characteristics of the device, and its application to maneuvering a fish robot. Observations and experimental analysis of the pectoral fins of a black bass (Micropterus salmoides) revealed that the locomotion of the fish, such as swimming forward at low speed, swimming backward, and turning in a horizontal plane is generated by using a combination of a feathering motion and a lead-lag motion of the pectoral fins. A mechanical pectoral fin making a feathering motion and a lead-lag motion generates a thrust force in a range of phase differences between both motions. The unsteady vortex lattice method, including the effect of viscosity, can express fairly well the unsteady forces acting on the mechanical pectoral fin in the range of phase differences where it exerts the thrust force. The fish robot, consisting of a model fish body and a pair of mechanical pectoral fins, can not only swim forward and turn in almost the same position, but can also swim in a lateral direction without changing the yaw angle. Translation of an article that appeared in the Journal of The Society of Naval Architects of Japan, vol. 182 (1997): The original article won the SNAJ prize, which is awarded annually to the best papers selected from the SNAJ Journal, JMST, or other quality journals in the field of naval architecture and ocean engineering.     

Minimum Efficient Scale (MES) and preferred scale of container terminals

The decision on the scale of a port terminal affects the terminal’s managerial, operational and competitive position in all the phases of its life. It also affects competition structures in the port in which the terminal is operating, and has a potential impact on other terminals. Port authorities and terminal operators need to know the scale of the terminal when engaging in concession agreements. In economic theory the scale of a plant/firm is typically defined in relation to the Minimum Efficient Scale (MES), the long-run output where the internal economies of scale are fully exploited. However, there are a number of theoretical and empirical indications that in ports the scale of a terminal is commonly guided by a combination of the MES and other determining factors. The “preferred” scale is the result of a complex interaction between the MES, the port governance framework and objectives, the market size and structure, technological change and operational considerations, physical and geographical limitations, and the business patterns of shipping lines. This study analyses the factors resulting in a preferred container terminal scale that in most of the times is different from the MES. The analysis of the technical, market-related and governance-related factors is supported by theoretical and empirical insights that illustrate the presence of a range of actual ”preferred” scales of terminal concessions that usually are different, below or above, MES.