船舶系统

船舶系统 船舶系统 ship system 船舶上的舱底和压载系统、甲板排水及疏水系统、空气测深注入系统、生活用水和供暖系统、灭火系统、生活污水系统、冷藏与制冷系统、空调和通风系统的统称     

数字化造船系统中的关键技术介绍

介绍数字化造船系统组成和系统中各个分系统包含的主要内容和关键技术,如设计制造系统、过程自动化系统、企业管理与电子商务系统、系统网络及系统平台。     

一体化海洋监测系统调试技术研究与应用

一体化海洋监测系统使用仪器和系统收集环境数据、平台位置、运动、稳性和锚链张力等,以支持作业者安全操作。该系统将采集、显示和存储半潜式平台各子系统的数据,集成了各种传感器和其它系统的数据,包括装载管理程序、环境监测系统、系泊监测系统交互、钢悬链线立管交互。研究结果将助推深水海洋平台海洋监测系统的全面国产化进程,提高系统的稳定性。     

基于PLC技术的船舶电力推进系统设计

传统的船舶电力推进系统存在着可靠度低的缺陷,为此提出基于PLC技术的船舶电力推进系统设计研究。电力推进系统主要由电力系统、调速系统、回转系统和推进器组成。系统硬件设计包括变频器、PLC硬件设备和变频器通信硬件设备设计,系统软件设计包括通讯环境设计、电力推进控制系统冗余程序设计和电机运行程序设计。通过系统硬件与软件设计实现了电力推进系统的运行。实验结果显示,设计的船舶电力推进系统的可靠度比传统系统高出25.2%,说明设计的船舶电力推进系统具备极高的有效性。     

电厂码头输煤系统的运行逻辑关系分析

电厂码头的皮带输煤系统,是一个包括码头卸煤系统、厂区上煤系统、筛碎系统、控制及报警系统、计量、采样、除铁、抑尘等多个工艺子系统的综合系统。本文以国外某百万千瓦级大型火力发电厂为例,对输煤系统中的各主要设备和辅助设备及工艺系统的运行逻辑关系进行研究和分析,并设计建立一套控制逻辑严密且具有智能化的自动控制系统,从而消除潜在的逻辑矛盾、程序漏洞和运行安全风险,进而使整套输煤系统的运行达到一个高效、智能、可靠、节能、稳定和安全的设计指标,以保障电厂维持较高生产效益。     

自升式钻井平台轮机特殊系统简介

自升式钻井平台是海上油气钻井钻探的主要装备,有可移动性好、用钢量少、造价相对低等特点。从泥浆简介、泥浆系统简介和系统原理方面简要介绍了自升式钻井平台上的泥浆系统,又分别从系统主旨、系统原理和系统特点方面简要介绍了冲桩系统。以泥浆系统和冲桩系统作为典型,表现了自升式钻井平台轮机特殊系统相对于普通船舶上的常规轮机系统的不同之处,明确指出了系统所服务的特殊对象,突出海工装备上轮机系统的特点。     

GPRS及其短距离无线采集控制系统

文中在现代测控系统中应用了短距离无线数传技术和GPRS无线数传技术,给出一个通用无线采集控制系统。该系统包括两子系统,现场无线通信子系统和GPRS远程无线通信子系统。在文中介绍了系统原理和结构,并详细讲述了系统的硬件设计、软件通讯协议和软件设计。本系统的创新之处本系统为远程采集和远程监控的通信系统提供了一个新颖实用的解决方案。此系统具有很强的通用性,不但可以应用于仪表的自动抄表系统,还可以应用于智能小区、安防、环境监测、海洋石油、国防等领域中,有着非常好的发展前景。     

防火安全要重视

1.要重视避雷系统的检测和维护保养港口、码头、库房和大型固定装卸机械按有关安全要求都安装有避雷系统,以保证这些建构筑物和设备免受可能的雷击损害。避雷系统一般由受电器(接闪器)、引下线和接地极组织构成一个严密完整的保护系统。如果该系统     

一种应用于综合舰桥系统的体系结构设计

论文以综合舰桥为研究对象,研究了综合舰桥系统体系结构的设计方案。从系统总体设计的角度,分析了综合舰桥系统的基本功能、组成要素、信息流程、连接方式、层次划分与设计规范,设计了包括运作体系结构、系统体系结构和技术体系结构的三维系统体系结构。其中运作体系结构规定了系统的任务与信息流程;系统体系结构界定了系统的组成元素和元素之间的连接方式;技术体系结构规定了系统设计应遵循的技术标准和规范。论本文提出的综合舰桥系统体系结构,为系统总体设计提供了理论框架。     

海上交通管理系统VTS的雷达信号处理技术

海上交通管理系统VTS在海上交通疏导、船舶管理、提升海上交通效率和安全方面发挥着重要的作用,交通管理系统VTS采集雷达系统、AIS系统、卫星系统的信号,通过分析和处理,获取船舶和航线的关键数据,因此,在VTS系统中,雷达信号的处理技术非常关键。本文首先介绍了海上交通管理系统的构成,设计了VTS的雷达信号处理系统,并对信号处理系统的硬件设备、信号处理过程进行了详细的分析。     

以功能为导向的舰船建造质量控制方法

长期以来,由于舰船建造工程浩大、过程复杂、工艺繁多,人们对于建造质量如何影响舰船可靠性缺乏系统性的研究。为实现对考虑建造质量影响的舰船可靠性的科学预测和有效控制,从舰船总体功能的角度出发,在现代造船模式背景下,针对舰船建造提出一种以功能为导向的质量控制（FOQC）方法。融合舰船目标功能、质量参数、建造工艺因素,提出舰船建造可靠性预测模型。建立工艺—质量参数及质量参数—特征功能可靠性模型,对预测模型进行量化计算,获得建造质量对舰船可靠性影响的定性与定量分析,并依据分析结果,对关键质量点与关键工艺环节进行控制与优化。以某舰船轴系安装为实例进行分析,验证了方法的可行性与有效性,可为舰船建造质量的定量化检验与评价提供基础性方法的原理指导。     

单体半滑行穿浪船船型与静水航行性能

半滑行穿浪船是一种结合了混合式内倾型穿浪船艏和半滑行式水下船体的高速单体穿浪船,同时具有穿浪船的穿浪特性和半滑行船的航行特性,拥有良好的快速性和适航性.半滑行穿浪船采用具有折角设计的压浪型干舷,折角线在船长方向上与水线之间存在夹角.压浪干舷具有抑制内倾型船舶的干舷上浪、提供升力、增加储备浮力和减摇的作用.通过基于动网格的数值计算,对压浪干舷的纵向倾角及优选纵向倾角下的半滑行穿浪船在静水中的航行特性进行研究.计算结果表明:拥有较小纵向倾角的压浪干舷的使用效果较好;半滑行穿浪船同排水型穿浪船相比其在高速段的阻力和姿态得到了很大改善.     

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.     

Numerical analysis on free surface waves and stern viscous flow of a ship model

This paper deals with numerical techniques for computing the viscous flow past a ship hull with and without a free surface using a Reynolds-averaged Navier-Stokes solver with global conservation. In the first technique, a coarse grid is used to find an approximate solution to the free surface problem. Interpolation of a fine grid is subsequently carried out, and a more exact solution, particularly in the boundary layer and wake, is obtained. In the second technique, a modified Baldwin-Lomax model is introduced to compute the viscous flow with and without a free surface. These numerical techniques are applied to simulations of the flow around a Series 60 and an SR196C ship model. The results are compared with measurement data, and the usefulness of the numerical techniques is demonstrated.     

A survey on modeling and control of thruster-assisted position mooring systems

This review presents a systematic summary of the state-of-the-art development of technological solutions, modeling, and control strategies of thruster-assisted position mooring (TAPM) systems. The survey serves as a starting point for exploring automatic control and real-time monitoring solutions proposed for TAPM systems. A brief historical background of the mooring systems is given. The kinematics and a simplified kinetic control-design model of a TAPM system are derived in accordance with established control methods, including a quasistatic linearized model for the restoring and damping forces based on low-frequency horizontal motions of the vessel. In addition, another two mooring line models, i.e., the catenary equation and the finite element method model, are presented for the purpose of higher-fidelity simulations. The basic TAPM control strategies are reviewed, including heading control, surge-sway damping, roll–pitch damping (for semisubmersibles), and line break detection and compensation. Details on the concepts of setpoint chasing for optimal positioning of a vessel at the equilibrium position are discussed based on balancing the mooring forces with the environmental loads and avoiding mooring line failure modes. One method for setpoint chasing is the use of a structural reliability index, accounting for both mean mooring line tensions and dynamic effects. Another method is the use of a lowpass filter on the position of the vessel itself, to provide a reference position. The most advanced method seems to be the use of a fault-tolerant control framework that, in addition to direct fault detection and isolation in the mooring system, incorporates minimization of either the low-frequency tensions in the mooring lines or minimization of the reliability indices for the mooring lines to select the optimal directions for the setpoint to move. A hybrid (or supervisory switching) control method is also presented, where a best-fit control law and observer law are automatically selected among a bank of control and observer algorithms based on the supervision of the sea-state and automatic switching logic.     

基于一个二维修正水弹性方法的集装箱船体梁动态前极限强度评估研究

海上极端波因其巨大的波高常常导致船体的极限破坏。该文提出了一个二维的修正水弹性方法来研究一个集装箱船船体梁在极端波中的动态前极限强度。传统的极限强度评估基于准静态方法,没有动态效应被考虑。而船体在波浪下的动态结构响应是基于水弹性方法,传统的水弹性方法并不能计算船体梁的动态非线性强度。该二维修正的水弹性方法考虑时域波浪和非线性船体梁之间的耦合,将水弹性方法和Smith方法结合,用Smith方法计算船体梁的刚度,而其刚度与船体梁的强度和变形曲率有关。所以该时域的非线性刚度被用于修改水弹性方法里的常数项的结构梁刚度。几组极端波模型被用以产生船体梁的大变形和非线性动态垂向弯矩。文中分别采用修正水弹性方法和普通水弹性方法,通过改变四个重要的极端波参数如极端波最大波高、规则波的波高、波速和波长等来研究其对船体梁船中处的大变形转角和非线性垂向弯矩的影响,通过采用修正的水弹性方法计算得来的结果与水弹性方法计算得来的结果相比较,得到了一些差异和结论。     

Integrated optimisation design of a dynamic umbilical based on an approximate model

An optimised design of a dynamic umbilical requires an extreme cross-sectional stress to be maintained within an allowable limit and a fatigue life to be guaranteed to be sufficient. It should be noted that a dynamic umbilical is a typical geometric bi-scale structural system. It consists of a local cross-sectional scale and a global configuration scale, which are significantly different in terms of geometric sizes. In this study, we established an approximate model to achieve an optimised design of the dynamic umbilical by considering the parameters of local cross-sections and global configurations simultaneously. The design variables of a dynamic umbilical are independently identified and defined at both local sectional and global configuration scales in the approximate model. Furthermore, we selected the maximum tension strain and the maximum bending moment, for covering local and global properties, as the objectives to be minimised. The approximate model was observed to be effective in integrating the local and global responses into one loop so that the computational efficiency could be significantly increased. We implemented the optimisation framework on a dynamic umbilical with a lazy-wave configuration, which is considered to be a basis for a case study. Furthermore, we verified the feasibility and effectiveness of the integrated optimisation strategy by numerical simulations. Moreover, we compared the optimised dynamic umbilical properties with those without optimisation. It was observed that the fatigue life of the optimised dynamic umbilical was improved significantly, thereby indicating that the integrated optimisation methodology provides a new model and algorithm for an efficient design of the dynamic umbilical.     

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.     

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.     

Vibration-assisted decommissioning of a slip joint: Application to an offshore wind turbine

An alternative option to the traditional grouted joint for wind turbines is a direct steel-to-steel connection, also known as slip joint. In a recently published work, a proof of concept of a vibration-assisted installation and decommissioning technique of a slip joint was illustrated. Leveraging on the obtained results, the current study shows for the first time a decommissioning campaign carried out using a vibration-assisted technique applied on a prototype hydraulic wind turbine tower located in the North Sea, and connected to the monopile through a slip joint. The key aspect of the dismounting procedure is a priori knowledge of the resonance frequency clusters corresponding to the slip joint’s cross-sectional modes. Therefore, field hammer tests and experimental modal analysis were carried out inside the wind turbine tower. The identified frequencies and mode shapes were then compared with numerical ones estimated by a finite element model of the investigated structure. The comparison showed that a set of frequency clusters can be directly selected from a detailed numerical model. The preparatory work of the slip joint decommissioning was then executed by installing electric shaker devices, based on the dynamic identification results, and hydraulic jacks mounted inside the wind turbine tower. A first decommissioning trial was carried out in May 2019, while the final decommissioning was performed in August 2019. After analysing the measurements of the hydraulic pressures, displacements and excitation frequencies during the decommissioning campaigns, the results showed that it is possible to disconnect the slip joint if, in combination to a vertical static force, one of the identified cross-sectional mode shapes is excited. The vibration-assisted decommissioning proved to be a successful technique to dismount the connection in a controlled and straightforward manner.