共查询到18条相似文献,搜索用时 9 毫秒
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沈忱张民辉苏孟超房卓姚海元 《港工技术》2021,58(5):94-98
LNG船舶通航因特殊监管要求,具有一定排他性。前期研究表明基于目前一般通航规则,单个港址LNG泊位数量不宜超过4个,超过后,船舶通航效率较低、运营监管风险较高。本文采用多智能体泊位组联合运营仿真建模,采用控制变量法,定量评估了码头高负荷状态下不同LNG船舶监管条件和航行距离对LNG运输船舶通航效率的影响,以及采用一定优化通航组织方式对通航效率提升的效果。结果表明,LNG泊位数量4个、独立单向航道、LNG船舶航行监管距离在20海里左右时,系统运营效率相对的较高;进一步采取LNG船舶组队进出港或设置独立双向LNG航道通航等缩短必要交通管制所占用航道时间的优化通航组织,对提高LNG船舶通航效率具有明显效果。研究成果可为LNG码头合理建设规模、LNG船舶通航组织优化及航行安全保障等提供参考依据。 相似文献
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曹妃甸LNG接收站作为我国北方天然气供应的重要保障主体,冬季高峰期月到港LNG船舶达到8~11艘,按照规划扩建后将成为国内外规模最大的LNG接收站。由于LNG船舶通航的严格监管,到港船舶数量的增加会对航道通航效率造成显著压力,因此需要论证码头建设规模与航道的适应性。在现状定线制通航条件下,基于多智能体仿真建模方法,构建曹妃甸港区LNG船舶进出港全过程仿真模型,定量评估不同LNG码头建设规模对LNG船舶通航效率的影响。结果表明,当LNG泊位数达到4个时,船舶进出港受制约明显,优化航路后能有效提高LNG船舶的通航效率。 相似文献
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为满足北方地区冬季LNG高峰期保供目标,部分渤海沿海港口在同一港池内规划布置双LNG泊位。鉴于双泊位联合运营下的LNG船舶关联性强且操纵难度高的特点,有必要对LNG双泊位联合运行进行调度管理方案研究。以国内首座正式投产运营的LNG双泊位为例,基于船舶操纵模拟仿真方法,通过分析LNG船舶航行对航道通航效率影响及相邻泊位联动性,提出双泊位运营下的LNG船进出港优先级。在此基础上,结合LNG双泊位运营特点和通航管理规则,制定近期和远期不同阶段的船舶联合调度组织模式。研究结论可为单港池LNG双泊位的通航管理提供决策依据。 相似文献
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舟山群岛海域规划有多个LNG重要港址,对于保障长三角天然气供应具有关键作用。LNG码头具有自身建设要求高和对外排他性强的特性,在舟山群岛海域为代表的开敞岛礁海域建设具有较大技术难度。以舟山六横和上海洋山LNG码头为例,系统分析开敞岛礁海域对LNG码头规划布置的影响,分析码头和航道布置关键问题,论证多个大型LNG泊位联合布置的安全间距,研究LNG船舶通航安全和通航效率影响,提出LNG码头规划布置方案。结果表明,开敞环境下布置多个大型LNG泊位时,与掩护条件较好时相比应适当增加安全间距,注意横风、横流以及斜顶流的影响,确保船舶通航安全,要控制LNG合理运输规模,采取通航优化措施,提升区域船舶通航效率。 相似文献
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LNG船舶通航管控要求严格,LNG进港船舶通航方式和应急锚地的设置一直是LNG码头港址选择和建设营运管理过程中重点关注的问题之一。通过对国内现有规范有关LNG船舶通航及锚地设置要求的梳理和沿海已建或在建代表性LNG接收站港址水域水文泥沙条件、航道锚地设置现状、实际建设营运情况及通航管理实践的分析,提出沿海不同港址LNG船舶全潮或乘潮通航方式选择及应急锚地布置建议,可为LNG接收站建设、运营和通航管理提供参考。 相似文献
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The planning, design and development of a container terminal with optimum size and capacity and with a minimum capital cost
is fundamentally dependent upon the loading and discharging operations at the quayside. The quayside function of container
terminals is dependent basically on the number of berths available to service the incoming container ships. The objective
of the container terminals dealing and admitting the ongoing ship calls is to provide immediate berth and loading and discharging
services to the container ships with a minimum costly waiting time and a maximum efficiency. Previously terminal planners
used to build extra berths to provide service. During the last two decades the terminal operators have adopted automation
technologies in loading and discharging operation of the container ships as an alternative to designing extra berths. Ship
owners naturally expect least waiting times for their container ships. On the other hand, it is also natural for port operators
in a container terminal with costly facilities to see a high berth occupancy and productivity at the quayside. This study
uses queuing theory to find a break-even point as a way of evaluating the cost of container ship waiting times and the cost
of berth unproductive service times for container terminals aiming to automate their quayside operation. The analysis illustrates
that automation devices installed on conventional Quayside Cranes (QSCs) significantly reduce the turnaround time of the container
ships calling at the ports. It argues, however, that there should be a balance between the cost of berth unproductive service
times and the cost of vessel waiting times. The study introduces a break-even point to be considered as a benchmark for calculating
such a balance. The analysis in this study can be used as a decision tool for the operators of container terminals in the
medium to small ports to appraise the feasibility of an investment in automation or expansion of the quayside facilities. 相似文献
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Recently, shipping lines have focused on efficient ship operation, which relates to energy efficiency issues in shipping and, particularly, to operational issues such that the minimisation of fuel consumption and resulting greenhouse gas emissions. Efficient ship operation in container lines is closely related to the ship’s time at sea and ship’s time in port. Reduction in port time, thanks to high-quality port operations, allows improvement in the operational efficiency of a liner service by reducing the fuel consumption of a ship at sea and its resulting CO2 emissions. The main goal of this article is to investigate how time in port affects efficient ship operation in terms of operating costs, CO2 emissions and externalities. For this, as a methodology, a simulation based upon system dynamics is introduced. Major finding is that less time in port resulting from the improvement of port operations contributes to efficient ship operation in terms of operating costs, amount of CO2 emissions and external effects in the liner shipping industry. In particular, a sensitivity analysis on efficient ship operation vis-à-vis the quality of port operation shows that bigger ships need to select highly productive calling ports that provide less time in port. 相似文献
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船舶在港口停泊或在过驳、动力定位作业过程中需要进行复杂的操纵,此时船舶需要在低速非设计工况下实现后退、紧急制动和紧急向前等运动。在这些低速操纵运动过程中,螺旋桨工作于四象限内,由此产生的侧向力会影响船舶的操纵性能。出于安全考虑,需要评估螺旋桨在四象限内的水动力性能。文章基于CFD方法模拟了螺旋桨在四象限内作业时的紧急制动和紧急向前工况,采取LES方法模拟了紧急制动和紧急向前时剧烈的非定常分离流动。对紧急制动工况进行了网格收敛性分析;所得到的推力和扭矩系数与现有的试验值进行了比较,分析了螺旋桨负荷对螺旋桨性能的影响。通过对桨叶表面的压力分布、一些典型平面上的速度轮廓和流线以及推力的频谱特性进行分析,展示了螺旋桨流动的机理。 相似文献
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The main challenge for container ports is the planning required for berthing container ships while docked in port.Growth of containerization is creating problems for ports and container terminals as they reach their capacity limits of various resources which increasingly leads to traffic and port congestion.Good planning and management of container terminal operations reduces waiting time for liner ships.Reducing the waiting time improves the terminal’s productivity and decreases the port difficulties.Two important keys to reducing waiting time with berth allocation are determining suitable access channel depths and increasing the number of berths which in this paper are studied and analyzed as practical solutions.Simulation based analysis is the only way to understand how various resources interact with each other and how they are affected in the berthing time of ships.We used the Enterprise Dynamics software to produce simulation models due to the complexity and nature of the problems.We further present case study for berth allocation simulation of the biggest container terminal in Iran and the optimum access channel depth and the number of berths are obtained from simulation results.The results show a significant reduction in the waiting time for container ships and can be useful for major functions in operations and development of container ship terminals. 相似文献