关于大风浪中船舶航行安全的综合分析

文章从船舶大风浪航行安全的角度出发,提出了人的因素对大风浪航行安全的影响以及大风浪操纵决策所需考虑的因素,并结合大风浪船舶的操纵方法和避碰理论,总结了许多可以借鉴的宝贵经验,力图保证船舶在大风浪中的航行安全.     

大风浪中船舶安全航行方法探讨

本文指出了船舶在大风浪中航行应该事先做好的准备,分析了船舶在大风浪中航行时常见的几种情况,探讨了在大风浪中船舶航行的几种基本的操纵方法,提出了在大风浪中操纵船舶的注意事项。     

浅析船舶在大风浪中的航行安全

为了提高船舶在大风浪中航行的安全性,本文通过分析大风浪天气对船舶安全的影响,提出了船舶在大风浪中航行的应对措施,以期对船舶在大风浪中的安全航行有所帮助。     

大风浪中航行系统的研究

此文针对船舶在大风浪中航行,提出一种新的航行系统。该系统从船舶在大风浪中运动机理出发,计算出船舶在大风浪中航行的运动谱,并建立耐波性综合评估方程,判断出船舶的航行安全状况。     

浅析海上风浪中船舶的行驶安全

大风浪是船舶航行的必遇挑战,也是船舶安全航行的潜在威胁。本文从安全角度出发,浅析在海上遇大风浪情况下,船舶安全行驶的各类因素,风浪前做好准备工作,从理论出发,联系实际,风浪中无畏无惧,夺得先机,在此基础上,举例说明了风浪中操船措施以及Z字法航线规划。     

基于航速保持的舵减摇控制方法

船舶航行受阻力影响引起航速和能量损耗。研究船舶在静水和波浪中的附加阻力,给出船舶航行时的总体航速损失的计算方法。设计带有航速损失约束的自动舵控制系统,依据舵角协同控制方法设计航向和舵减摇滑模控制规律。综合讨论"航向"与"航向+减摇"两种工作情况,包括横摇稳定、航向精度、航速保持、操舵能量消耗。仿真结果表明:该方法可以有效保持航速;从航行经济性的角度,对于同时安装有减摇鳍和自动舵的船舶,不推荐采用舵鳍联合减摇的控制方法。     

大风浪中船舶航行安全性评价

从船舶在波浪中运动的机理出发，将模糊数学中的层次分析法理论用到大风浪中船舶航行安全性评估上来，开发了相应的计算程序。寻找到了船舶在波浪中航行时的安全航态范围和在某一航速(或航向)时的最佳航向(或航速)，形成了一套“理论航法”，使得驾驶员在操纵船舶时能够得到有效的指导。     

HATLAPA A4V型舵机跑舵故障一例

舵装置，是船舶重要航行设备。跑舵指没有操舵信号时舵机自行转动，进出港、过运河、过船闸等船舶机动航行时危及航行安全。     

随浪中船舶舵效损伤试验研究

本文报道了船舶随浪航行时舵横向力模型试验，以静水中船后舵横向力为参照基准，分析了船舶位于波面不同位置处的舵效损伤及其原因，并试图说明，舵效损伤是船舶随浪航行发生横甩的一个重要原因。     

随浪中船舶舵效损失试验研究

本文报道了船舶随浪航行时舵横向力测量模型试验。以静水中船后舵横向力为参照基准，分析了船舶位于波面不同位置处的舵效损失及其原因。并试图说明，舵效损失是船舶随浪航行发生横甩的一个重要原因。     

恶劣海况下船舶航向控制仿真及应用研究

船舶在海面航行时,会受到风浪的干扰.此时,船舶航向控制困难,操舵频繁.采用Kalman滤波和模糊自整定PID控制,并基于线性化船舶运动方程的线性时,不变连续时间系统的设计方法得到的船舶操纵控制器,具有抗干扰能力强、鲁棒性好的特点,有效地解决了船舶在风浪干扰条件下的船舶航向控制时的操舵频繁与无效操舵问题.     

风帆辅助推进船舶操纵可控区研究

加装风帆后的船舶在低速时的航行特性有别于无帆情形。为确保低速航行安全,基于MMG非线性运动方程,计算了有、无风帆情况下的船舶操纵可控区。运动方程中的船体水动力系数、舵模块参数等由经验公式得到,帆/船整体气动力系数由基于滑移网格方法的CFD手段获得。计算结果表明:不同帆攻角下的船舶自由操控区不同,通过合理的帆/舵联合操纵,可以扩大风帆辅助推进船舶低速航行的可自由操控区,增强其在风中的抗风能力。     

A study on improving the course-keeping ability of a pure car carrier in windy conditions

The course-keeping ability of a pure car carrier (PCC) in windy conditions is discussed in this article. Numerical simulations of two PCCs were carried out to compare their course-keeping abilities in wind. The two PCCs had the same hull form but different types of rudder. One PCC was fitted with a semispade rudder (hereinafter, the normal rudder), whereas the other was fitted with a spade-type Schilling rudder (hereinafter, the Schilling rudder). Both PCCs were designed to a new concept for the accommodation structure and hull form above the load water line. In this new design concept, there are no sharp corners in the superstructure so as to reduce wind resistance and improve steering performance. The limits of course keeping for the two PCCs were investigated through simulations. The course-keeping abilities of the two PCCs, each with two different types of autopilot system, were also investigated in wind. To develop the numerical simulation, the hydrodynamic coefficients of the two PCCs were predicted based on the data published for a third PCC having similar principal particulars. The numerical model of the two PCCs was validated by comparing its behavior with the respective full-scale trial results. Wind resistance coefficients were predicted by combining the results of wind tunnel experiments of the object PCCs and a regression model. Numerical simulations under steady wind conditions were also carried out and the results compared with some full-scale experiments to validate the mathematical model of the PCC.     

基于分数阶PIλDμ的船舶航向控制

船舶在海上航行时受到海风、海浪和海流等环境扰动作用,这造成在不同航速下船舶动力学模型的参数不确定性,本文对船舶本体运动和风浪流干扰进行建模,提出一种基于分数阶PIλDμ的抑制风浪干扰的的航向控制算法,并与传统 PID算法进行对比,针对某型船舶动力学模型在6级海风和5级海浪海况下进行对比数字仿真。仿真结果表明,该算法在不同航速下具有较好的控制品质和鲁棒性,对风浪干扰具有良好的适应性,可应用于船舶的航向控制,易于工程实现。     

船舶操纵模拟器操纵仿真数学模型

系统地论述了船舶操纵仿真数学模型。包括船舶操纵基本模型、水动力、螺旋桨推力及扭距、主机扭距、舵力及其力矩、风、浪、流、锚、缆、拖轮的作用力、浅水影响及侧壁效应,最后给出了主要仿真结果和主要结论     

Comparison of the mariner Schilling rudder and the mariner rudder for VLCCs in strong winds

A simulation model of a very large crude carrier (VLCC) with either a mariner type Schilling rudder or a mariner rudder was developed from captive and free-running model tests. Kijima’s regression formula was used to predict the hydrodynamic hull forces on the VLCC. To simulate full-scale maneuvering at cruising speed, the constant torque operation of the main engine was assumed. Considering the higher normal lift force and maneuverability of the mariner type Schilling rudder as compared to the mariner rudder, the size of mariner type Schilling rudder is kept smaller as compared to mariner rudder. To compare the efficiency of the two types of rudder system, maneuvering simulations at constant engine torque and course-keeping simulations at various gusting wind speeds and encounter angles were carried out. Based on the simulation results, the two rudder types were compared from the viewpoint of maneuvering and fuel efficiency in windy conditions.     

船舶航向非线性控制系统仿真研究

基于Bech模型并充分考虑舵机特性提出了一种结构简单的船舶航向控制器--TC控制器.介绍了船舶非线性模型的选取,描述了船舶舵机特性,在此基础上设计了TC控制器.通过参数整定实验确定了TC控制器各参数的取值,并进行了航向改变、航向保持及参数摄动仿真实验.仿真结果证明所设计的船舶航向控制器效果良好,具有较强的鲁棒性.     

最小推进功率要求对舵面积预估的影响

针对由于能效设计指数规则要求背景下最小推进功率导则的实施对舵面积预估产生影响的问题,分析中小型液货船新船开发设计阶段预估舵面积必须考虑的因素,提出采用公式推导舵面积预选取值,并经过液货船实例试验验证,可以同时满足相关规则以及操纵性的要求,中小型液货开发中基于最小保持航向速度估算舵面积是合理而且可行的.     

基于电子海图的船舶操纵仿真器

本文主要介绍最近研制的由微机、高分辨率显示器、图形卡、操纵控制箱等组成的基于电子海图船舶操纵仿真器的两个主要技术──船舶操纵数学模型和电子海图技术，最后还介绍了该仿真器在航海实际中的一个应用．在数学模型中，考虑到航海实际的需要，提出了一个适合常速、低速和大漂角等各种情况的水动力计算模型以及四象限舵力和浆力的算法．另外，考虑了浅水、岸壁、风、流、浪的影响及附属操纵设备──拖轮、缆绳、锚链等对船舶的作用．本仿真器的电子海图装置，不仅能实时显示船舶所在海域的海图，动态显示船舶的二维俯视图象及运动姿态、航行轨迹，还可根据需要选择性地放大、缩小海图、显示各种岸基设施，并且可以记录模拟过程中的各种数据，制作航迹图的硬拷贝以及在显示器上再现，以供分析研究．     

Prediction of ship steering capabilities with a fully nonlinear ship motion model. Part 1: Maneuvering in calm water

This paper introduces a new method for the prediction of ship maneuvering capabilities. The new method is added to a nonlinear six-degrees-of-freedom ship motion model named the digital, self-consistent ship experimental laboratory (DiSSEL). Based on the first principles of physics, when the ship is steered, the additional surge and sway forces and the yaw moment from the deflected rudder are computed. The rudder forces and moments are computed using rudder parameters such as the rudder area and the local flow velocity at the rudder, which includes contributions from the ship velocity and the propeller slipstream. The rudder forces and moments are added to the forces and moments on the hull, which are used to predict the motion of the ship in DiSSEL. The resulting motions of the ship influence the inflow into the rudder and thereby influence the force and moment on the rudder at each time step. The roll moment and resulting heel angle on the ship as it maneuvers are also predicted. Calm water turning circle predictions are presented and correlated with model test data for NSWCCD model 5514, a pre-contract DDG-51 hull form. Good correlations are shown for both the turning circle track and the heel angle of the model during the turn. The prediction for a ship maneuvering in incident waves will be presented in Part 2. DiSSEL can be applied for any arbitrary hull geometry. No empirical parameterization is used, except for the influence of the propeller slipstream on the rudder, which is included using a flow acceleration factor.