采用高阶边界元法的楔形体变速度入水数值模拟(英文)

A high order boundary element method was developed for the complex velocity potential problem. The method ensures not only the continuity of the potential at the nodes of each element but also the velocity. It can be applied to a variety of velocity potential problems. The present paper, however, focused on its application to the problem of water entry of a wedge with varying speed. The continuity of the velocity achieved herein is particularly important for this kind of nonlinear free surface flow problem, because when the time stepping method is used, the free surface is updated through the velocity obtained at each node and the accuracy of the velocity is therefore crucial. Calculation was made for a case when the distance S that the wedge has travelled and time t follow the relationship s=Dtα, where D and α are constants, which is found to lead to a self similar flow field when the effect due to gravity is ignored.     

多种激励耦合作用下的二维液舱晃荡(英文)

In this research,liquid sloshing behavior in a 2-D rectangular tank was simulated using ANSYS-FLUENT software subject to single or multiple-coupled external excitations(such as sway coupled with roll,and sway and roll coupled with heave).The volume of fluid(VOF) method was used to track the free surface of sloshing.External excitation was imposed through the motion of the tank by using the dynamic mesh technique.The study shows that if the tank is subjected to multiple coupled excitations and resonant excitation frequencies,liquid sloshing will become violent and sloshing loads,including impact on the top wall,will be intensified.     

海底犁式挖沟机犁体曲面优化设计(英文)

The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the towing force of a vessel. A multi-objective genetic algorithm based on analytical models of the plow surface has been examined and applied in efforts to obtain optimal design of the plow. For a specific soil condition, the draft force and moldboard surface area which are the key parameters in the working process of the plow are optimized by finding the corresponding optimal values of the plow blade penetration angle and two surface angles of the main cutting blade of the plow. Parameters such as the moldboard side angle of deviation, moldboard lift angle, angular variation of the tangent line, and the spanning length are also analyzed with respect to the force of the moldboard surface along soil flow direction. Results show that the optimized plow has an improved plow performance. The draft forces of the main cutting blade and the moldboard are 10.6% and 7%, respectively, less than the original design. The standard deviation of Gaussian curvature of moldboard is lowered by 64.5%, which implies that the smoothness of the optimized moldboard surface is much greater than the original.     

舰船刚性阻振质量复合托板隔振特性优化设计(英文)

In considering the theory of structural dynamic optimization design, a design method of the structural style of ship composite brace with rigid vibration isolation mass was studied. Two kinds of structural dynamic optimization formulations minimizing the vibration acceleration of the non-pressure hull on the restraining condition of the gross weight of the ship cabin were established: 1) dynamic optimization of the sectional dimensions of the rigid vibration isolation mass in the composite brace; 2) dynamic optimization of the arranging position of the rigid vibration isolation mass. Through the optimization results, sectional dimensions and the arranging position of the rigid vibration isolation mass with better performance in reducing vibration were gained, and some reference was provided for practical engineering designs as well as enrichment of the design method of a novel ship vibration-isolation brace.     

爆炸破片穿透舰船舷侧防护水舱剩余特性研究

为了抵御水下武器对舰船结构的毁伤,大型水面舰船在舷侧要设置多层防护结构。针对破片对防护水舱的毁伤情况以及破片穿透水舱的剩余特性问题,应用ABAQUS软件,采用耦合欧拉—拉格朗日方法,数值模拟了不同形状、不同质量、不同长细比的爆炸破片穿透舰船舷侧防护水舱,特别是背水钢板的演变过程。通过对数值试验结果的分析得到了爆炸破片穿透舷侧防护水舱剩余特性的规律。研究表明,球状破片的剩余速度要比柱状破片的剩余速度大得多,并且破片细长比也是影响破片剩余速度的重要因素。     

液舱晃荡与浮体非线性耦合运动分析(英文)

Nonlinear interactions among incident wave, tank-sloshing and floating body coupling motion are investigated. The fully nonlinear sloshing and body-surface nonlinear free surface hydrodynamics is simulated using a Non-Uniform Rational B-Spline (NURBS) higher-order panel method in time domain based on the potential theory. A robust and stable improved iterative procedure (Yan and Ma, 2007) for floating bodies is used for calculating the time derivative of velocity potential and floating body motion. An energy dissipation condition based on linear theory adopted by Huang (2011) is developed to consider flow viscosity effects of sloshing flow in nonlinear model. A two-dimensional tank model test was performed to identify its validity. The present nonlinear coupling sway motion results are subsequently compared with the corresponding Rognebakke and Faltinsen (2003)’s experimental results, showing fair agreement. Thus, the numerical approach presented in this paper is expected to be very efficient and realistic in evaluating the coupling effects of nonlinear sloshing and body motion.     

大型LNG船液舱晃荡结构动响应研究(英文)

文章首先采用非线性有限元方法研究了No.96型LNG船液舱围护结构的极限承载能力,详细分析了不同边界条件下的失效模式。然后采用显示积分方法研究了不同晃荡压力峰值和持续时间的晃荡冲击载荷作用下液舱围护系统结构动响应,得到了不同工况下结构的动态失效特性。最后,回归了基于比例极限和突变永久变形的临界压力载荷公式,并给出了液舱围护系统结构设计准则和安全性评估方法建议。     

爆炸荷载作用下的舰船防护舱壁的承载能力(英文)

大型水面舰船的防护舱壁需要设计成工作在薄膜应力状态下.利用能量法推导了在爆炸荷载作用下防护舱壁塑性大变形的计算公式、探讨了防护舱壁的最大承载能力,对防护舱壁的设计要求进行了讨论.与国外发表的有关试验结果进行了计算比较,结果表明该方法具有一定的应用价值.     

应用RANS(雷诺平均的纳维尔一斯托克斯方程)和动量理论进行螺旋桨诱导速度的计算研究(英文)

In order to provide instructions for the calculation of the propeller induced velocity in the study of the hull-propeller interaction using the body force approach,three methods were used to calculate the propeller induced velocity:1) Reynolds-Averaged Navier-Stokes(RANS) simulation of the self-propulsion test,2) RANS simulation of the propeller open water test,and 3) momentum theory of the propeller.The results from the first two methods were validated against experimental data to assess the accuracy of the computed flow field.The thrust identity method was adopted to obtain the advance velocity,which was then used to derive the propeller induced velocity from the total velocity field.The results computed by the first two approaches were close,while those from the momentum theory were significantly overestimated.The presented results could prove to be useful for further calculations of self-propulsion using the body force approach.     

舰船维修系统建模与能力评估(英文)

The authors developed a prototype of a warship maintenance system. The process started by defining the maintenance requirements of warship equipment. Next, a planning scheme was development for a maintenance network. An optimization target for the plan and indexes for assessment were established. Based on the above work, a simulation model was proposed with two layers: a base and a workshop. Dispatching rules were then formulated for the simulation. Experimental results proved the validity of the model and the dispatching algorithm. It was found that the model can solve the capacity evaluation problem for maintenance systems and provides a scientific basis for decision-maker to make decisions regarding equipment maintenance.     

舰船密闭舱室火灾模拟及防火设计

对舰船内部密闭舱室这一典型结构的火灾及火灾安全设计进行研究，并对密闭舱室内火灾发生后的蔓延情况进行了模拟计算，得出其火灾蔓延规律，总结出该类型结构的防火设计应该注意的方面，其结论能够对舰船内部密闭舱室及类似结构的防火设计起到帮助作用。     

战斗部舱内爆炸对舱室结构毁伤的实验研究

  目的  为了研究箱型梁典型节点结构在舱内爆炸下的结构强度,  方法  基于ANSYS/LS-DYNA显式动力有限元软件,首先建立箱型梁船体舱段结构的有限元模型。然后,采用ALE算法开展舱内爆炸载荷下舷侧箱型梁与强横梁连接处不同型式节点结构的动态响应数值计算。最后,在给定的炸药当量和爆点位置情况下,获得舱室结构的整体变形和破坏模式,并分析在不同节点结构设计方案下典型位置的应力特征。  结果  \t\t计算结果表明：舷侧箱型梁与强横梁连接处圆弧式和肘板式节点结构的应力峰值与甲板破口尺寸基本相当;从舱壁撕裂长度来看,肘板式稍逊于圆弧式,在中间箱型梁与强横梁连接处,圆弧连接最优,单侧肘板次之,双侧肘板最差。  结论  \t\t 所得到的数值计算结果可为箱型梁节点连接结构的工程应用提供有益的参考。     

改善全封闭水面舰艇舱室空气品质技术初探

改善舰艇舱室空气品质至关重要,目前国内没有合适的舰用空气净化设备,通过借鉴国外和我国民用空气净化设备及技术特点,探讨了有效改善全封闭水面舰艇舱内空气品质的途径.明确指出开发船用空气净化设备势在必行,对舱室内的空气进行消毒净化处理也是舰艇空调系统设计发展的必然趋势.     

一种自锁式舱门的结构设计与分析

目前,舰载设备中的舱门普遍采用电机或机械挡块的结构形式实现舱门开关状态的控制,主要存在使用和维保成本高、结构占用空间大、解锁不便利等问题,在实际应用中存在诸多不便。为解决上述问题,本文设计开发了一种自锁式舱门,并对舱门的结构和工作原理进行设计和分析,同时采用理论计算的方式对主要零部件进行计算和校核。此外,采用Simulate进行仿真计算,对舱门的主要零部件进行强度和刚度仿真分析,验证了方案的可行性。     

基于AHP和满意度评价的舰船生活区舱室布置评估

针对舰船生活区舱室布置评估这一复杂性和模糊性高且准则不易量化的决策问题进行深入研究,运用AHP(Analytic Hierarchy Process)法进行评估准则体系的赋权分析。在AHP法分析的基础上,引入满意度的概念并运用专家评分法进行综合评判。在详细叙述这一评估方法流程的基础上,通过舰船生活区舱室布置设计评估的算例进行方法可行性论证。分析结果表明,该方法具有良好的可行性和准确性,同样适用于其他区域舱室布置和总布置评估问题。     

仿真技术在舰船设计研究中应用

文章论述了仿真的概念及其在舰船设计研究中的应用,分别对推进系统、舰船航态及船舶电力系统仿真进行了介绍,分析了该技术在国内外的现状及发展方向,提出了我国在这方面应努力的方向。     

舰船安全性设计和管理的探索实践

论述了舰船安全性设计和管理的概念及发展趋势，对应用舰船安全性设计和管理进行了介绍，分析了舰船安全性设计和管理在探索实践中需重点关注的方面，提出了在该方面开展研究的设想。     

舰船概念设计发展趋势

随着舰船系统的日益复杂,更新舰船设计理论及方法就成了迫切需要解决的问题.本文在对国外舰船概念设计理论及方法的研究现状进行分析的基础上,对我国舰船概念设计进行总结,得出数学船、多学科间耦合作用分解以及多学科优化将会是未来我国发展舰船概念设计综合集成系统需要解决的关键技术难题.     

舰船总体设计流程分析

为提升船舶动力工程的总体正向设计能力,研究船舶动力系统工程的数字化设计方法。将基于模型的系统工程（MBSE）方法理论与系统工程方法进行融合,基于自主研发的V-Dats软件平台和图形化的SysML语言,从发电机组辅助系统的需求、行为、结构和参数4个维度进行建模,完成了系统需求—功能—逻辑—物理的过程分析,得到了系统需求架构、功能架构及物理架构模型,并在系统层级开展了闭环验证和确认。通过总结船舶动力工程总体设计流程的体系顶层框架,提出了基于MBSE的总体正向设计方法,研究成果可有效支撑船舶动力工程总体论证与设计。     

舰艇作战系统设计中的折衷分析

舰艇作战系统设计是一个自上而下不断调整的过程,系统设计的折衷分析又是其中很重要的一个环节。本文针对作战系统设计中得出的各种功能和技术因素,从计算机系统结构、作战指挥方式和作战室结构等几个方面进行了分析,得出了折衷分析的结果,对舰艇作战系统的设计具有一定的理论参考价值。