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1.
Environmental issues and rising fuel prices necessitate better energy-efficiency in all sectors.The shipping industry is one of the major stakeholders,responsible for 3% of global CO2 emissions,14%-15% of global NOX emissions,and 16% of global SOX emissions.In addition,continuously rising fuel prices are also an incentive to focus on new ways for better energy-effectiveness.The green ship concept requires exploring and implementing technology on ships to increase energy-efficiency and reduce emissions.Ship operation is an important topic with large potential to increase cost-and-energy-effectiveness.This paper provided a comprehensive review of basic concepts,principles,and potential of operational options for green ships.The key challenges pertaining to ship crew i.e.academic qualifications prior to induction,in-service training and motivation were discussed.The author also deliberated on remedies to these challenges.  相似文献   

2.
FPSO关键系统风险分析(英文)   总被引:2,自引:0,他引:2  
Risk analysis of key systems have become a growing topic late of because of the development of offshore structures. Equipment failures of offloading system and fire accidents were analyzed based on the floating production, storage and offloading (FPSO) features. Fault tree analysis (FTA), and failure modes and effects analysis (FMEA) methods were examined based on information already researched on modules of relex reliability studio (RRS). Equipment failures were also analyzed qualitatively by establishing a fault tree and Boolean structure function based on the shortage of failure cases, statistical data, and risk control measures examined. Failure modes of fire accident were classified according to the different areas of fire occurrences during the FMEA process, using risk priority number (RPN) methods to evaluate their severity rank. The qualitative analysis of FTA gave the basic insight of forming the failure modes of FPSO offloading, and the fire FMEA gave the priorities and suggested processes. The research has practical importance for the security analysis problems of FPSO.  相似文献   

3.
一种新型水下管道连接器的结构设计与优化(英文)   总被引:1,自引:0,他引:1  
The basic configuration of a new type of subsea pipeline connector was proposed based on the press-fitting principle,and a parametric finite element model was created using APDL language in ANSYS.Combining the finite element model and optimization technology,the dimension optimization aiming at obtaining the minimum loading force and the optimum sealing performance was designed by the zero order optimization method.Experiments of the optimized connector were carried out.The results indicate that the optimum structural design significantly improved the indicators of the minimum loading force and sealing performance of the connector.  相似文献   

4.
At present,equivalent water depth truncated mooring system optimization design is regarded as the priority of hybrid model testing for deep sea platforms,and will replace the full depth system test in the future.Compared with the full depth system,the working depth and span are smaller in the truncated one,and the other characteristics maintain more consistency as well.In this paper,an inner turret moored floating production storage & offloading system(FPSO) which works at a water depth of 320m,was selected to be a research example while the truncated water depth was 80m.Furthermore,an improved non-dominated sorting genetic algorithm(INSGA-II) was selected to optimally calculate the equivalent water depth truncated system,considering the stress condition of the total mooring system in both the horizontal and vertical directions,as well as the static characteristic similarity of the representative single mooring line.The results of numerical calculations indicate that the mathematical model is feasible,and the optimization method is fast and effective.  相似文献   

5.
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.  相似文献   

6.
This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations. The whole engine system is divided into several functional blocks: cooling, lubrication, air, injection, combustion and emissions. The sub-models and dynamic characteristics of individual blocks are established according to engine working principles equations and experimental data collected from a marine diesel engine test bench for SIMB Company under the reference 6M26SRP1. The overall engine system dynamics is expressed as a set of simultaneous algebraic and differential equations using sub-blocks and S-Functions of Matlab/Simulink. The simulation of this model, implemented on Matlab/Simulink has been validated and can be used to obtain engine performance, pressure, temperature, efficiency, heat release, crank angle, fuel rate, emissions at different sub-blocks. The simulator will be used, in future work, to study the engine performance in faulty conditions, and can be used to assist marine engineers in fault diagnosis and estimation(FDI) as well as designers to predict the behavior of the cooling system, lubrication system, injection system, combustion, emissions, in order to optimize the dimensions of different components. This program is a platform for fault simulator, to investigate the impact on sub-blocks engine’s output of changing values for faults parameters such as: faulty fuel injector, leaky cylinder, worn fuel pump, broken piston rings, a dirty turbocharger, dirty air filter, dirty air cooler, air leakage, water leakage, oil leakage and contamination, fouling of heat exchanger, pumps wear, failure of injectors(and many others).  相似文献   

7.
In this paper,an underwater vehicle was modeled with six dimensional nonlinear equations of motion,controlled by DC motors in all degrees of freedom.Near-optimal trajectories in an energetic environment for underwater vehicles were computed using a numerical solution of a nonlinear optimal control problem(NOCP).An energy performance index as a cost function,which should be minimized,was defined.The resulting problem was a two-point boundary value problem(TPBVP).A genetic algorithm(GA),particle swarm optimization(PSO),and ant colony optimization(ACO) algorithms were applied to solve the resulting TPBVP.Applying an Euler-Lagrange equation to the NOCP,a conjugate gradient penalty method was also adopted to solve the TPBVP.The problem of energetic environments,involving some energy sources,was discussed.Some near-optimal paths were found using a GA,PSO,and ACO algorithms.Finally,the problem of collision avoidance in an energetic environment was also taken into account.  相似文献   

8.
The virtual erection simulation system was explained for a steel structure including ship and ocean plant blocks.The simulation system predicted the erection state to optimize any gap or overlap of blocks based on 3-D measurement data.The blocks were modified(cut) on the basis of the simulation result on the ground before erecting them by crane.The re-cutting process was not required and the blocks were erected into a mother ship speedily.Therefore,the erection time is reduced,increasing the dock turnover.  相似文献   

9.
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.  相似文献   

10.
系泊系统非线性恢复力研究及其应用(英文)   总被引:1,自引:1,他引:1  
Mooring system plays an important role in station keeping of floating offshore structures.Coupled analysis on mooring-buoy interactions has been increasingly studied in recent years.At present,chains and wire ropes are widely used in offshore engineering practice.On the basis of mooring line statics,an explicit formulation of single mooring chain/wire rope stiffness coefficients and mooring stiffness matrix of the mooring system were derived in this article,taking into account the horizontal restoring force,vertical restoring force and their coupling terms.The nonlinearity of mooring stiffness was analyzed,and the influences of various parameters,such as material,displacement,pre-tension and water depth,were investigated.Finally some application cases of the mooring stiffness in hydrodynamic calculation were presented.Data shows that this kind of stiffness can reckon in linear and nonlinear forces of mooring system.Also,the stiffness can be used in hydrodynamic analysis to get the eigenfrequency of slow drift motions.  相似文献   

11.
集装箱码头物流路径优化研究   总被引:5,自引:1,他引:4  
根据集装箱码头的工艺流程,提出了集装箱码头物流路径优化模型。该模型以集卡行走里程最短为目标,在满足集装箱堆场堆存要求和船舶装卸作业要求的情况下,求解集卡最优行走路径。算例计算表明,该优化模型可为码头管理者提供一定决策帮助。  相似文献   

12.
螺旋桨流固耦合多目标优化设计   总被引:1,自引:0,他引:1  
本文提出将NSGA-Ⅱ多目标优化算法应用于螺旋桨多目标优化设计,并通过面元法和有限元法实现螺旋桨流固弱耦合.通过计算安装在Seiun-Maru(一艘日本散货船)上的HPS大侧斜螺旋桨压力系数分布和压力脉动,考虑了流固耦合效应的计算精度要高于不考虑流固耦合效应,验证了考虑流固耦合的必要性.本文以螺旋桨效率、非定常力和重量作为目标函数,在满足水动力性能、结构响应和空泡性能等约束条件下,选取描述螺旋桨外形的6个参数作为设计变量,以此建立优化函数.在不同近似最优解和非设计点为初值的算例中,其结果均改善了所有目标函数,验证了本文方法的有效性、适用性和鲁棒性.本文提出的多目标优化方法将有助于提高设计效率,节省计算资源,可成为未来螺旋桨设计的有效工具.  相似文献   

13.
工程应用中在进行鲁棒性优化设计时,要求所求出的解既要具有较高的质量,又要满足一定的鲁棒性要求。将鲁棒性优化问题转化为一个双目标的优化问题,即一个目标为解的最优性,另一个目标为解的鲁棒性,并针对一艘最大应力接近许用应力的多用途船进行基于鲁棒性的中横剖面优化设计。首先,用支持向量机的方法建立船体舱段的近似模型,用于求取舱段的最大应力,并结合蒙特卡罗积分的思想构造出表示最大应力鲁棒性的函数;随后,以最大应力最小和最大应力的鲁棒性函数值最小为目标函数,设计出一种求解鲁棒性最优解的粒子群多目标优化算法。优化结果不仅能降低船体结构的最大应力,同时还可较大程度地提高最大应力的鲁棒性,证明了该方法的可行性。  相似文献   

14.
进度、费用和质量为工程项目的3大主要控制目标,工程项目多目标优化就是要尽可能实现3大目标的和谐统一。利用多目标优化理论建立了面向工程项目的多目标优化模型,给出了利用向量评价遗传算法对工程项目多目标优化问题的求解设计思路,阐述了算法的实现流程,并通过实例验证了该模型有效解决工程项目多目标优化的可行性。  相似文献   

15.
纵倾优化下的船舶能效数值模型   总被引:1,自引:0,他引:1  
刘伊凡  张剑  张跃文 《船舶工程》2015,37(12):31-34
通过Fluent数值计算和Simulink建模仿真的方法,建立船舶的CFD计算模型及能确定转速(n)-航速(V_s)-船舶能效营运指数(EEOI)间对应关系的船舶能效准稳态仿真模型,进而分析不同工况下纵倾变化对船舶营运能效的影响。以定转速航行模式的46000t油轮为目标船,经模型的计算和船模试验的验证,发现适当纵倾可提高目标船的营运能效。结合相关海事公约法规,计算目标船的最佳纵倾在艉倾2.61m处,可降低EEOI达0.8%。  相似文献   

16.
针对船舶初始设计阶段船舶操纵性能优化这一复杂的多目标问题,开展相应的多目标优化方法研究。利用Pareto方法的特点,提出基于Pareto遗传算法来解决传统方法中的这个问题。经过优化可以得到均匀分布的Pareto解集,便于进行分析比较和选择,并给出计算实例。  相似文献   

17.
控制船舶轴系纵向振动的动力吸振器参数优化研究(英文)   总被引:1,自引:0,他引:1  
在船舶轴系中安装动力吸振器是减小船舶轴系纵向振动的有效方法,而动力吸振器的参数合理优化配置是控制轴系纵向振动的重要手段。将船舶轴系等效为多自由度系统,基于有限单元法建立船舶轴系纵向振动运动模型,并通过加装动力吸振器用于控制船舶轴系纵向振动。运用重分析方法求解轴系运动方程得到推力轴承处的力传递率和能量传递率,将二者作为评价动力吸振器对轴系振动控制效果的指标。在研究轴系响应频率范围内,提出将求解全局最优解较强的遗传算法与多目标优化算法相结合以优化动力吸振器参数;并且研究特定共振峰消减的参数优化问题。最后通过算例,比较不同目标函数以及动力吸振器不同安装位置对轴系纵向振动控制的影响,验证文中优化算法的可行性。  相似文献   

18.
针对基本蚁群优化算法在物流配送路径优化应用过程中存在的问题,主要是由信息素全局和局部更新策略而导致车辆选择路径时容易陷入局部最优解的现象,本文详细研究了蚁群算法的改进算法,即最大最小蚁群算法;并引入信息素平滑机制来提升算法的路径探索能力,实现此组合优化理论在带时间窗的车辆路径问题中的应用.  相似文献   

19.
水面舰船对轻量化和抗爆性能均有特殊的需求,而这两个目标此消彼长的关系又使得实现它们的途径相互矛盾。为找到能同时提高轻量化和抗爆性能的满意解,建立以板厚为变量的多目标优化模型。在优化过程中,通过参数化建模技术实现建模的自动化,数值模拟采用船体三舱段有限元模型,使用ABAQUS/EXPLICIT求解器进行非线性有限元分析,并在优化流程中引入实验设计和近似模型进行响应预报,在此基础上,还通过NSGA-II遗传算法进行多目标优化,得到优解。通过对优化后的船舯舱段与优化前的进行对比分析,发现重量和抗爆性能这两个目标分别有0.46%和22.51%的改进,实现了轻量化和抗爆性能的双向提升。  相似文献   

20.
优化选择的船舶主尺度方案需要具有较好的经济性、技术性能,而博弈论是研究解决、优化决策选择的科学,根据船舶主尺度方案优选问题与经济学中博弈问题之间的相似性,从博弈的观点确定了船舶设计中的博弈方及其对应的策略空间,即各设计目标视为博弈问题博弈方;设计变量集合视为所有博弈方的战略集组合,从而提出了船舶主尺度方案优选设计问题的博弈方法。通过实例应用表明,合作博弈论方法能更好地综合反映设计目标的要求,优选结果更加合理。  相似文献   

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