共查询到20条相似文献,搜索用时 109 毫秒
1.
风帆助航是船舶节能减排的重要途径。本文以1条鱿鱼钓船作为研究对象,根据该船的特点选择NACA0006型帆和圆弧型帆作为辅助风帆,然后利用Fluent软件建立所选风帆模型,对这2种风帆的空气动力性能进行数值模拟计算。根据软件的计算结果估算风帆助航时鱿鱼钓船的每年节油量以及所减少的二氧化碳排放量。通过对风帆助航鱿鱼钓船的稳性进行计算分析,可以确定只要合理地安装和操作风帆,风帆助航渔船是能满足稳性要求的。 相似文献
2.
船舶气象导航最省燃料航线研究 总被引:3,自引:3,他引:0
船舶气象导航是保证船舶航行安全和节能的重要手段。本文应用最佳控制理论研究和建立船舶最省燃料航线数学模型。在分析比较船舶最短时间航线和最省燃料航线数学模型的基础上,讨论了最省燃料航线算法实现。并针对冬季北太平洋进行了最省燃料航线模拟试验。 相似文献
3.
4.
Cargo ship designs offered by shipbuilders differ in characteristics such as deadweight, speed, fuel consumption and cargo equipment. The best vessel for high freight markets and high fuel prices may not be the best for low freight markets and low fuel prices. A model has been developed to compare by simulation a number of multi-purpose general cargo vessels suitable for the trade of a Turkish shipowner. The model simulates the operation of each vessel under a variety of operating scenarios, e.g. fuel prices and freight profiles over the ships' lives, and estimates the distribution of resulting net present values. The techno-economic simulation model incorporates variables including ship size, speed, first cost, fuel consumption, load factor and port days.
Results are presented for six standard vessels of around 20 000 dwt operating over a long and a short route. Although the ranking of the six varies with assumptions, one design is shown to be superior under most operating conditions. 相似文献
Results are presented for six standard vessels of around 20 000 dwt operating over a long and a short route. Although the ranking of the six varies with assumptions, one design is shown to be superior under most operating conditions. 相似文献
5.
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
6.
分析了船舶"航线设计"项目教学和评估中存在的问题,探讨解决问题的可行性。按照岗位要求完善航线设计的步骤,改进航路资料的教学方法,增加学生动手的机会,提高学生的动手能力,并提出了适应岗位要求的"航线设计"项目的教学方法和评估方法。 相似文献
7.
文章建立了S型铺管船的船体、托管架和管线动态耦合模型。考虑了海浪、风和海流载荷作用下以及动力定位系统的控制下,分析时域内管道对船舶运动和受力特点的影响。主要包括:建立起重铺管船的动力定位运动模型,建立基于碰撞-接触原理的V型托辊和托管架模型,设计具有PID伺服系统的张紧器模型,提供连接托管架和船尾的非线性弹性铰接模型。进行时域动态模拟得到结果,通过与非铺管作业工况下的运动响应的对比表明,管线对船舶横摇运动影响较大,对纵摇和垂荡运动有一定程度的影响;管道对船舶纵荡、横荡和艏摇三个自由度上的受力影响极大。 相似文献
8.
Ying Wang 《Maritime Policy and Management》2018,45(1):3-18
Due to the increase in trade from Korea to Central Asia, an efficient intermodal route for transporting cargo is important. Intermodal routing for long-distance transportation faces operational challenges, such as customs clearance, track gauge differences, and climate limitations. The initiative of the Silk Road Economic Belt recently proposed in China could improve trade and transport links in Asia and create an efficient transportation route that focuses on the railroad service provided in China. The objective of this study is to obtain an evaluation structure for intermodal routing and then find the route for transporting cargo from Korea to Central Asia under China’s Silk Road Economic Belt with integrated Fuzzy Delphi and Fuzzy (Elimination Et Choice Translating Reality (ELECTRE) I methods. After a sensitivity analysis is performed, development strategies and alternative routes are suggested. The results show that among the five principal factors, total cost is the most important factor for logistics companies when they select a transportation route, followed by reliability, transportation capability, total time, and security. Of the sub-factor weights, transportation costs and cooperation and emphasis among state organization are important. In the intermodal route results, route 3, Incheon to Qingdao to Horgos to Almaty, is preferred. 相似文献
9.
10.
This paper presents a novel forward dynamic programming method for weather routing to minimise ship fuel consumption during a voyage. Compared with traditional weather routing methods which only optimise the ship’s heading, while the engine power or propeller rotation speed is set as a constant throughout the voyage, this new method considers both the ship power settings and heading controls. A float state technique is used to reduce the iterations required during optimisation and thus save computation time. This new method could lead to quasi-global optimal routing in comparison with the traditional weather routing methods. 相似文献
11.
12.
13.
14.
为获得水路运输中船舶的最佳航速,实现燃油效率的最大化,以长江航线货运船的航速、燃油等真实监测数据为基础,提出一种新的船舶航速与油耗优化模型。模型包括白箱模型(White-Box Model,WBM)和黑箱模型(Black-Box Model,BBM)两个部分:WBM由改进后的物理方程和数学公式组成;BBM是BP(Back Propagation)神经网络。两者结合成新的灰箱模型(Grey-Box Model,GBM)。通过分析船舶航行过程中影响船舶燃油消耗的多种因素,确定WBM参数,分别用串联和并联的方式将白箱与BP网络结合构建船舶航速与油耗优化模型,采用牛顿-拉普森迭代算法进行求解。计算结果表明:优化模型可在选定的航段内找到最佳的指导航速,并且模型的R2达到了0.945。此外,将建立的模型与单一的WBM进行对比验证,所建立的船舶航速与油耗优化模型得到的最佳航速更加精确,整体误差也从0.130减小到0.071。 相似文献
15.
With the effects of global warming, the Arctic is presenting a new environment where numerous ice floes are floating on the open sea surface. Whilst this has improved Arctic shipping navigability in an unprecedented way, the interaction of such floes with ships is yet to be understood to aid the designing of ships and route planning for this region. To further explore this topic, the present work develops a procedure to derive an empirical equation that can predict the effects of such floes on ship resistance. Based on a validated computational approach, extensive data are extracted from simulations of three different ships with varying operational and environmental conditions. The ice-floe resistance is shown to strongly correlate with ship beam, ship buttock angle, ship waterline angle, ship speed, ice concentration, ice thickness and floe diameter, and the regression powers of each of the parameters on resistance are ascertained. This leads to a generic empirical equation that can swiftly predict ice-floe resistance for a given ship in a given condition. Subsequently, demonstrations are given on the incorporation of the derived equation into a set of real-time Arctic ship performance model and voyage planning tool, which can predict a ship's fuel consumption in ice-infested seas and dynamically suggest a route with the least safety concern and fuel consumption. Moreover, the equation is validated by providing ice resistance prediction for experimental and full-scale conditions from multiple sources, showing high accuracy. In conclusion, the empirical equation is shown to give valid and rapid estimates for ice-floe resistance, providing valuable insights into ship designs for the region, as well as facilitating practical applications for polar navigation. 相似文献
16.
17.
为了满足10 kV舰船中压直流综合电力推进系统对于高效率、高功率密度中压推进变频器的需求,本文分析了现有多电平拓扑的特性与适应性,提出了两种适用于开绕组多相电机的10kV推进变频器拓扑结构:五电平有源中点箝位(ANPC)/H桥拓扑以及对称混合九电平拓扑。两种拓扑结构使用的悬浮电容和开关器件数量完全相等。本文分析了这两种拓扑的工作原理和调制策略,分别建立了开关函数模型,并得出了母线中点电压和悬浮电容电压在理想情况下均可保持自平衡的结论。分别搭建了这两种拓扑的小功率样机并进行了实验验证。 相似文献
18.
This paper presents theoretical and numerical study on bending properties of unbonded flexible risers. To capture nonlinearities in layer's sliding, the stress component due to slip-stick behavior is considered and energy conservation principle considering sliding-caused heat consumption is employed in the analytical model. Besides, a finite element model estimating mechanics of unbonded flexible risers' bending is proposed. In the finite element model, couplings between bending moment–curvature and axial stress as well as contact interaction among layers and tendons have been considered. The theoretical and numerical results were validated against the corresponding experimental data in literature and mutually compared in analyzing nonlinear bending behavior of flexible risers. Moreover, the impacts of axisymmetric loads on riser's bending behavior have been further investigated. 相似文献
19.
以上海海事大学教学实习船"育明"轮为对象,研究船舶加装风帆装置的船体结构强度问题,通过局部加强风帆基座和船体连接部分来保证风帆安装部位的结构稳定性。利用Solidworks和Femap软件建立了风帆基座和船体的有限元模型,计算得到该模型在10级风载荷下受风角度从0°~60°的应力和应变。最终结果表明,在10级风载荷下,该船风帆基座和局部加强后的船体的强度符合要求。 相似文献
20.
Toshifumi Fujiwara Grant E. Hearn Fumitoshi Kitamura Michio Ueno Yoshimasa Minami 《Journal of Marine Science and Technology》2005,10(3):131-146
The steady sailing performance of a sail-assisted bulk carrier is investigated utilising towing-tank derived hydrodynamic derivatives and wind tunnel measured aerodynamic properties of the sails and the ship. The aerodynamic characteristics investigated include the ship hull at the fully-loaded draught, the sail–sail interaction effects for two sets of four identical hybrid-sails, and the sail–hull interaction effects for the same two sets of identical sails in the presence of the selected bulk carrier hull-form. This is in addition to lift–drag measurements of single isolated sails of each shape. The form of the two sets of soft sails was rectangular and triangular. This paper is concerned with assessing the benefits of a sail-assisted ship operation, and hence a steady-state rather than complete time-domain integrations of the governing equations are reported. The results of the completed analysis suggest that the benefits of the derived sail generated driving force are greater than the overhead of equipping the ship with a selected system of hybrid-sails. Sail-assisted ships could represent an important contribution to an improving global environment by reducing the demands for a driving force through the propeller. 相似文献