粤东船舶定线制测量中水位控制的实施

针对2014年粤东水域船舶定线制扫测项目海域范围大、潮汐类型变化明显、布站困难的现实,经分析论证和数据试验验证,采用基于潮汐模型和余水位监控法实施水位控制。验证表明,该方法所提供的测区水位数据不仅能满足相关技术标准的精度要求,而且可以提高作业效率、降低作业成本与风险。水位控制的实施过程都贯穿着"分析论证、质量控制"的作业思路,可推广应用至其他测量任务。     

船舶最佳航线计算研究

本文提出了一种基于最优化原理的船舶最佳航线计算方法.在计算方案中引用了统筹学中求主要矛盾线的“破圈法”,并实现了计算网络和初值的自动选取,对不同浪、流条件下航行速度的变化作了定量估计,为船舶定线和跟踪服务提供了客观定量的计算方法,经过个例运算和实船试验,证明该计算方法是行之有效的.     

第九讲 天气定线中的等时线法和动态规划法

根据气侯材料选择最佳航线,即所谓气侯定线法,在缺少水文气象情报和预报的洋区以及预报时效不够的情况下,确有一定的效果;但在天气和海况复杂多变的地区应用这种方法选取最佳航线则困难颇多,效果并不甚理想。随着海洋资料情报增多、要素预报时效延长和预报精度的不断提高,越来越倾向于采用天气定线的方法,即根据未来天气情况确定最佳航线。在天气定线中应用最早的,首推基于图表计算的等时线法,其实质简述如下。 假定一具有技术速度V_0的船从A点出发,在无风和浪的情况下经过△t时间后,到达中心位于A、半径为V_0△t的圆弧上的某一点。但是,在大洋上航行的船处于各种水文气象条     

船舶随浪运动稳性仿真计算

本文利用Ｌｉａｐｕｎｏｖ理论，研究了船舶在规则波浪运动的稳性；利用摄动理论，求解出船舶运动响应；并讨论了船舶横摇与垂荡运动频率、最大横摇角和波浪要素对稳性曲线ＧＺ的影响，以及流体动压力对稳性曲线的修正，从而给计算船舶在随浪中的稳性提供了一种方法。     

电子海图的航海安全效益

每天进出美国港口的油轮达数百艘,其他船舶达数千条。这些船舶装载的货物和搭乘的乘客对美国经济十分重要。美国所消耗的石油的一半,对外贸易的90％以上(按重量计)都是由船舶运输的。由此也带来了客、货轮各类事故较为频繁。搁浅、碰撞和触礁等事故占美国海域海上航行事故的大部分,每年造成数10亿美元     

船舶随浪运动隐性仿真计算

本文利用Ｌｉａｐｕｎｏｖ理论，研究了船舶在规划波良运动的稳性；利用摄动理论，求解出船舶运动响应；并讨论了船舶横摇与垂荡运动频率、最大横摇角和波浪要素对稳性曲线ＧＺ的影响，以及流体动压力对稳性曲线的修正，从而给计算船舶在随浪中的稳性提供了一种。方法。     

船舶自动气象站分类标准及仪器布设原则

此文在研究分析各类船舶的基础上,对船舶自动气象站(船舶站)的基本构成和采集要素进行了分类,提出了船舶站构成的分类标准,解决了不同船舶选取安装不同要素自动站选择依据不足的问题,详述了船舶站的构成。以典型船舶站为例,详述了温、压、湿、风、降水、能见度、辐射等观测要素的安装位置选择,为船舶站的设计和安装提供参考依据。     

影响我国近海航海的水文气象要素气候分析

本文分析了影响航海活动的我国沿海水文气象要素风、浪、能见度、台风的时空分布及以这些要素为指标所作的近海航海气候区划。得到了我国沿海不同海区航海条件的特征和近海各个航海气候区航海条件的差异及对其的评价，这些结果对近海航海活动很有意义。     

矢量海图通告改正自动处理方法研究

在分析了国内外矢量海图通告改正技术现状的基础上,重点研究了实现矢量海图通告改正所必需的通告符号与海图要素自动转换、改正位置自动计算、改正要素自动匹配等自动处理方法,并举例说明了矢量海图通告改正的自动处理过程。     

海洋预报广播简介

海洋预报即将在中央电视台及中央广播电台播出,为了便于广大用户更好地使用海洋预报;了解各种要素预报产品制作的技术细节以及采取广播的形式和内容,现按预报要素分别简介如下: 一、海 浪 预 报 海浪是海面上一种比较复杂的波动现象,它影响着海上活动诸方面。大浪直接威胁着船舶航行的安全,并影响其航行速度。自五十年代中期起,利用海浪和其它水文气象要素的预报,选择船舶最佳航线,已取得显著的经济效益。     

动力定位船舶二阶低频慢漂力模型试验研究

对一艘动力定位船舶二阶低频慢漂力进行了模型试验,并将试验得到的纵向慢漂力谱、横向慢漂力谱与势流理论方法得到的理论值进行比较,结果表明,该模型试验方法与理论计算较为吻合。可为动力定位系统的设计和应用提供参考。     

A decision-making system to maritime risk assessment

In this study, we propose a fuzzy approach in order to evaluate the maritime risk assessment applied to safety at sea and more particularly, the pollution prevention on the open sea. The work is based on the decision-making system, named MARISA, presented in Balmat et al. (2009). This system allowed defining a risk factor for each ship according to ship’s characteristics and weather conditions. In this novel paper, the proposed system takes into account the ship speed evolution and the ship position with respect to maritime shipping lanes is developed. To validate the method, we present an example of results with real data.     

Propulsion system with flexible/rigid oscillating fin

The purpose of this paper is to describe the feasibility research on an oscillating fin propulsion control system as a vehicle actuator. The system is designed and constructed in order to be combined with ship models. Tank cruising tests are conducted to confirm the system's feasibility. As a result, several advantages of the oscillating fin system are found. A neural network is successfully applied for an identification of the ship model with the oscillating fin, and its effectiveness is confirmed     

GPSRTK技术在舰船抗冲击试验中的应用

在舰船实船海上抗冲击试验中，需要对爆源与被试舰的相对位置关系进行实时定位监测。对基于GPSRTK技术的试验定位系统的设计思路、工作原理、数据处理方法、组成与实现等方面进行了阐述，最后介绍了系统应用效果。     

Estimation of the Roll Hydrodynamic Moment Model of a Ship by Using the System Identification Method and the Free Running Model Test

When a fast container ship or a naval vessel turns, accompanying roll motions occur. This roll effect must be considered in the horizontal equations of the motion of the ship to predict the maneuverability of the ship properly. In this paper, a new method for determining a model structure of the hydrodynamic roll moment acting on a ship and for estimating the hydrodynamic coefficients is proposed. The method utilizes a system identification technique with the data from sea trial tests or from free running model (FRM) tests. To obtain motion data that is applied to the proposed algorithm, an FRM of a large container ship was developed. Using this model ship, standard maneuvering tests were carried out on a small body of water out of doors. A hydrodynamic roll moment model was constructed utilizing the data from turning circle tests and a 20-20 zig-zag test. This was then confirmed through a 10-10 zig-zag test. It was concluded that a model structure of the hydrodynamic roll moment model could be established without difficulty through a system identification method and FRM tests.     

Dynamic Response of the U-Typed Sandwich Panel Under Explosion Load Based on the SDOF Method

Sandwich panel is commonly used in ship and marine engineering equipment, such as side structure and superstructure deck of a ship, which is of good anti-explosion performance. This paper addresses a study on the dynamic response of the U-typed sandwich panel under explosion load through the numerical simulation and theoretical methods. Based on the orthotropic plate theory, the U-typed sandwich panel is simplified and transformed into a single degree of freedom (SDOF) spring system, the equivalent motion equation of the SDOF system and the expression of triangular explosion load function are established based on the SDOF theory, and the maximum response spectrum of the SDOF system is obtained. Then, the response of the equivalent SDOF system of the U-typed sandwich panel under explosion load is analyzed, and the theoretical results match well with the numerical simulation results, which verifies the accuracy of the theoretical method proposed in this paper. The theoretical method proposed in this paper could have good engineering applications for the structural anti-explosion design, and provide a reference for the evaluation of the anti-explosion performance of ship and offshore platform structures.

     

波浪作用下缆船拖带系统非线性运动数值模拟

基于船舶操纵性运动方程和拖缆的三维动力学运动方程,提出了被拖点位置匹配的方法,建立了拖船—拖缆—被拖船系统整体非线性拖带动力学模型。为了考察被拖船航向稳定性与横向稳性的关系以及波浪载荷作用的影响,被拖船采用水平面四自由度运动方程,并引入了波浪的作用力和力矩。拖船采用PD控制方法较真实地模拟了拖船航向改变的运动过程。对一个拖船—拖缆—被拖船系统(5 000 t的拖船和3 000 t的被拖船)在时域内进行了规则波浪作用下拖带运动的模拟,计算结果表明被拖带船舶在波浪中运动呈现运动稳定、不稳定和临界状态3种可能的特性。根据模拟计算结果,认为波浪中拖带航向稳定是被拖带船舶保持稳性的必要条件。     

A 3D fully coupled analysis of nonlinear sloshing and ship motion

This study investigates the coupling effects of six degrees of freedom in ship motion with fluid oscillation inside a three-dimensional rectangular container using a novel time domain simulation scheme. During the time marching, the tank-sloshing algorithm is coupled with the vessel-motion algorithm so that the influence of tank sloshing on vessel motions and vice versa can be assessed. Several factors influencing the dynamic behavior of tank–liquid system due to moving ship are also investigated. These factors include container parameters, environmental settings such as the significant wave height, current velocity as well as the direction of wind, wave and flow current acting on the ship. The nonlinear sloshing is studied using a finite element model whereas nonlinear ship motion is simulated using a hybrid marine control system. Computed roll response is compared with the existing results, showing fair agreement. Although the two hull forms and the sea states are not identical, the numerical result shows the same trend of the roll motion when the anti-rolling tanks are considered. Thus, the numerical approach presented in this paper is expected to be very useful and realistic in evaluating the coupling effects of nonlinear sloshing and 6-DOF ship motion.     

海上轻型高架索补给系统的力学分析及安全性研究

海上补给对保障后勤维护,保证战斗力提供了强大的物质、技术基础,因此,我国对海上货物传送装置的研发做了大量的工作并取得了较大的成果。但是对于小型舰艇编队的补给系统,尚处于起步阶段。基于此,在大型高架索补给系统的基础上,文中针对小型船艇的高架索补给装置的安全性进行了研究,确定其力学模型并提出了在海上施工过程中的补给系统的安全分析模型,为研制开发一种简便易行、高效经济的针对小型船艇进行补给的综合系统提供了技术基础。     

浮式生产储油船船体疲劳计算

船体结构的疲劳问题一直是船舶设计者十分关注的问题，特别是高强度钢在船体结构中的广泛使用，使船体结构的疲劳破坏问题更加突出。本文以一大型浮式生产储油船（Floating Production and Storage and Offilading)为例，系统地介绍了一种基于S－N曲线和Miner线性疲劳累积损伤原理，计算船体在局部结构应力热点处的疲劳寿命。该方法考察了船舶运营期内的实际工况和海况条件，船体局部应力热点的焊接情况，几何形状，受载形式以及尺寸效应等因素。计算中借助了DNV船级社的SESAM程序系统的部分模块。