不同舵速对船舶回转性能影响理论与试验分析

为分析不同舵速对船舶回转性能的影响,采用理论仿真和模型试验相结合的方法,基于流体力学和船舶操纵性基本理论,建立三自由船舶运动模型,对模型进行仿真验证。通过构建自航模试验系统,进行不同舵速下的自航模试验,理论与试验结果表明:不同舵速对战术直径、定常回转直径和横距无明显影响,但对纵距影响较明显。     

波浪中船舶操纵横摇预报及舵效影响分析

基于经典MMG模型建立操纵性和横摇四自由度耦合模型,并利用耦合模型叠加波浪力的方式,论文对一艘S175自航船模进行波浪中操纵性和横摇预报,并根据自航模试验进行对比验证;其波浪力采用三维面元法计算,并根据船舶实时速度和遭遇浪向进行二维插值。在验证模型准确性后,对船舶在不同舵速、浪向角下的操纵运动进行时域模拟,比较了舵速和遭遇浪向对船舶舵效的影响,分析了浪向、波频对船舶操纵和回转时横摇的影响。     

基于减摇鳍辅助回转的船舶操纵性能研究

基于MMG分离式建模思想，考虑作用在船体、螺旋桨、舵、鳍的水动力作用，建立双桨双舵船舶四自由度非线性数学运动模型，对某船模在静水中的回转性能进行仿真分析，将单独舵控制的仿真结果与船模试验结果进行了验证和分析，并对比了单独舵控制和舵、鳍联合控制下的回转性能，结果表明鳍参与控制回转时能明显缓解回转过程中的横倾。     

一艘装有回转导管工作船的模型操纵性试验

本文用模型试验方法讨论了装有回转导管工作船的操纵性。对装有回转导管及装有舵的船舶进行了比较试验,同时也对三种不同面积的平衡叶及三种尾呆木切割状态进行了模型试验。通过分折可以得出如下结论:1.装有回转导管的工作船的回转性能比装有舵时为好,倒航时尤为显著。2.变化装于回转导管后面的平衡叶面积,对船舶回转性能无显著影响。3.在相同舵角下,装有回转导管的船舶在稳定回转时的速降大于装有舵时的速降,但在同一无因次角速度下,两者速降一致。4.呆木割除后,船的相对回转直径显著减小,小舵角时更为明显,但航向稳定性随之变差。     

进江船型半悬挂舵升力性能优化

针对进江船型操纵性要求较高而半悬挂舵升力性能较低的问题,基于CFD方法,采用翼型优化设计、制流板优化设计、随边直尾化设计3种技术措施对一型“曼谷型”集装箱船的半悬挂舵进行升力性能优化。对比升力系数和阻力系数计算结果;考察舵面流动和端部流动,分析增升原因;结合阻力因素考虑,确定实船应用的优化舵系方案。结果表明：3种技术措施均可有效提高半悬挂舵的升力性能。通过对比原船型和目标船型的操纵性试验结果,验证了实船应用的优化舵系对于改善目标船型操纵性的作用。     

船舶旋回时的横倾

船舶旋回过程中的横倾是影响船舶安全的重要因素.为了研究重心较高的船舶在旋回过程中的横倾,文章根据分离型建模思想,建立了考虑船舶横倾的船舶运动数学模型,并利用MATLAB仿真软件仿真了船舶旋回运动,仿真结果与实验结果基本一致,说明模型正确.利用此模型对船舶旋回运动研究结果表明:船舶横倾角与GM值、船速和舵角有关;船舶旋回时应适当控制船速以减小横倾角,GM值较小的船舶还应控制船舶旋回时的舵角,从而保证船舶安全.     

转舵速度对舰船回转性能的影响

在忽略操舵引起速降的假设前提下,利用操舵响应方程对不同转舵速度下船舶的回转性能进行理论分析,获得定常回转直径、纵距、横距、战术直径等参数与转舵时间之间的近似关系。进而利用计及速降的非线性操纵性运动方程进行同一舰船不同转舵速度下的回转运动仿真,以及操纵性能和航速相同而船长不同的各船在不同转舵速度下的回转运动仿真。仿真结果与理论分析结果一致,均表明定常回转直径不受转舵速度的影响,纵距、横距、战术直径均随着转舵速度的提高而减小,且转舵速度对船长较短的舰船影响较大。     

分离式舵对潜艇横倾控制仿真分析

阐明分离式舵及差动舵角的定义,并以某型潜艇为例,分析了分离式舵对潜艇横倾的控制能力。并在此基础上编制了基于分离式舵的潜艇自动舵仿真模拟软件,通过仿真模拟对分离式舵与普通十字舵在潜艇高速回转时对横倾的控制能力进行了比较。     

转舵速度对船舶操纵性影响研究

采用MMG分离式水动力模型作为船舶操纵运动数学模型，编写MATLAB程序进行操纵性仿真预报，结合一艘双桨双舵船舶在设计航速下的定常回转运动进行了数值模拟，分析了船在不同转舵速度的回转运动轨迹和相应参数，进而得出转舵速度对船舶操纵性的影响规律。     

潜艇高速空间旋回运动分离舵横倾控制的数值研究

基于RANS方法,以全附体SUBOFF潜艇模型为研究对象,采用重叠网格嵌套滑移网格技术处理潜艇-舵相对运动,对不同螺旋桨转速下的潜艇空间旋回运动时的横倾控制开展研究。计算结果表明,分离舵的横倾控制效果较好,潜艇横倾角能迅速和平稳地过渡到静横倾角,实现了潜艇无横倾状态下的高速空间旋回运动,保障了潜艇姿态安全。分离舵的横倾控制对潜艇初期回转性能存在不利影响,但对定常回转性能的影响较小。     

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.     

高速排水艇回转性能估算

建立并求解高速排水艇稳定回转的运动方程。对运动方程中裸船体和附体的水动力导数、舵作用力和力矩、多个螺旋桨对回转的影响等进行估算。并以120t级渔政船为例，进行稳定回转直径和横倾角的计算，并与实船的试航结果进行比较。     

基于体积力法的半悬挂舵和全悬挂舵回转性对比

针对半悬挂舵和全悬挂舵回转性能差异问题,建立用于模拟螺旋桨推力的体积力模型,评估两种不同形式舵的回转性。对标模KCS船型回转运动进行计算流体动力学（Computational Fluid Dynamics,CFD）模拟,船后螺旋桨作用使用体积力模型替代。开展半悬挂舵回转性CFD模拟,并与试验结果对比验证。设计全悬挂舵并模拟其回转性,与半悬挂舵回转性进行比较。结果显示,半悬挂舵除战术直径与试验结果相差9.48%外,其他回转特性参数与试验结果相差均在3%以内,说明基于体积力法模拟回转性具有较高的可信度。全悬挂舵的回转特性参数均优于半悬挂舵,说明全悬挂舵的回转性能更佳。     

船舶在波浪中操纵运动仿真

本文研究了双浆双舵船在规则波中的回转运动，首先进行了约束模型试验，得到了操纵运动数学模型中的水动力系数，然后，进行了静水操纵运动数值仿真，并与自航模型试验结果进行了比较。最后，预报船舶在规则波中的回转运动，对一些影响回转运动的因素进行了讨论。     

Study on the maneuverability of a large vessel installed with a mariner type Super VecTwin rudder

The suitability of the Mariner type Super VecTwin rudder (hereinafter, the MSV rudder) for a large vessel is assessed in this article. Several experiments in a maneuvering pond were carried out and their results analyzed and summarized. Free-running tests such as turning, zigzag, and stopping tests were carried out with a 4-m free-running model of a very large crude carrier (VLCC) ship with the MSV rudder and the Mariner rudder. The results were compared to validate the maneuverability of a VLCC-sized a ship installed with the MSV rudder. A mathematical model of an MSV rudder is proposed for maneuvering simulation of a large vessel. To develop a maneuvering simulation for the model ship that was used in the free-running tests, hydrodynamic coefficients were estimated based on Kijima's regression formula. The coefficients of interaction between the hull and rudder (t_R, a_H, x_H) were obtained from a self-propulsion test in a towing tank. The complicated flow around the rudders is simplified to model the flow speed around the rudders. This simplified flow speed is utilized to compare the time histories of the free-running tests with the simulations. The mathematical model of the MSV rudder was further improved using the results of this comparison.     

船舶最小回转半径

本文确定了动稳定船舶的最小定常回转半径,进而就可把最优化方法应用于船舶操纵性设计中去。 基于线性化操纵运动方程,在优化过程中,把船体诸形状参数和舵面积作为设计变量,把回转性指数的倒数作为目标函数,把动稳定准则c′作为优化的约束条件。 根据计算结果,本文清晰地阐明了船体某些形状参数及舵面积的变化对最小回转半径的影响。     

船舶回转性能分析

在对船舶作回转性能分析时，采用战术直径表征其他回转特征量，计算出不同舵角、航速、纵倾及排水体积下的回转圈战术直径。衡量各因素对战术直径的影响程度，总结战术直径随各因素变化的规律，得到不同排水量之间战术直径的简化算法，为试航回转试验的特征量从设计吃水转化为满载吃水提供了一种较简捷的近似换算方法。     

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.     

返回原航迹机动的优化方法

返回原航迹机动在航行中营救落水者、海上搜救、扫布雷等舰船机动中经常被使用,但目前所采用的方法系属常规方法,尚未计及风、流、浪等因素的影响,对大多数船舶而言亦存在精度问题。本文结合船舶操纵运动数学模型,充分考虑到船舶的特性和环境因素影响,利用优选法选择操舵时机,以提高船舶返回原航迹机动的精度。     

常规海运船型开发中舵面积的预选研究与验证

船舶操纵性是船舶的重要指标,然而各船级社近期相继删除了其规范中对舵面积的强制要求。本文基于对操纵性理论的分析和总结,对常规运输船舵面积的确定进行了方法上的探讨,为方便数值分析对吃水、舵面积比等进行了统一定义,根据系列船资料拟合出修长度与舵面积比的关系曲线,并根据操纵性试验结果对87000t散货船进行了舵面积和舵形优化讨论,在此基础上梳理出舵面积的开发思路,即舵面积比应与船体修长度在较小时成负相关关系,但当修长度大过某一数值时,需要相对较大的舵面积比。在进行货船初步开发设计时,可根据修长度数值分析结果,选用合适的舵形和舵面积。