开口螺钉断裂的材料分析及工艺试验

制动夹钳单元中开口螺钉在高寒环境使用时发生断裂,对断裂的螺钉进行了断口分析,并对所使用2Cr13材料的热处理工艺进行了试验分析,检测不同温度下材料的冲击功,系统研究分析开口螺钉在低温下出现脆性断裂的原因并提出该零部件材料适用于低温的技术指标。     

动车组运营速度由350km/h提升至400km/h可行性研究

为了进一步提升人们乘坐高铁的出行体验和服务质量,提高运输组织效率,降低运营成本,中车长春轨道客车股份有限司拟研发400 km/h高速动车组。文章结合我国科技部"先进轨道交通"重点专项"时速400公里及以上高速客运装备关键技术"项目研究成果,主要从运行能力、安全性、舒适性、经济性等角度着重探讨动车组运营速度由350 km/h提升至400 km/h的可行性。     

地铁钛酸锂电池车载储能系统研究

以轨道交通车辆车载储能系统为对象,对当前应用于轨道交通车辆中的超级电容、高能电容和锂离子电池等车载储能元件的性能进行对比分析,得出钛酸锂电池具有高功率密度、高能量密度、高可靠性的技术特点。结合钛酸锂电池的性能特点和控制策略的研究,通过项目应用实例和现场试验对比,阐述了钛酸锂电池在地铁车辆储能系统中大规模应用的技术优势和广阔前景。     

高铁桥梁全封闭声屏障降噪性能试验与数值研究

为探明铁路桥上全封闭声屏障的降噪性,选取铁路桥上不同车速的混凝土全封闭声屏障、金属全封闭声屏障和单侧直立式声屏障测试断面,开展声屏障内外声场的噪声测试,建立全封闭声屏障统计能量分析模型,结合实测结果验证数值模型的适用性,最后对比分析声屏障不同结构形式、隔声板材料和传声损失、车速对声屏障降噪量的影响,探讨声屏障数值模型中...     

一种车辆段用多回路分时充电系统的设计

储能式有轨电车上线运营前需在车辆段将车载储能系统快速充满电,文章提出一种车辆段用多回路分时充电控制的地面充电系统,介绍了系统组成和工作原理,重点分析了多回路分时充电的控制策略.应用情况表明该充电系统运行稳定,车辆充电资源调度合理,可满足储能式有轨电车运营需求.     

Dynamic optimization of ship energy efficiency considering time-varying environmental factors

Nowadays, optimization of ship energy efficiency attracts increasing attention in order to meet the requirement for energy conservation and emission reduction. Ship operation energy efficiency is significantly influenced by environmental factors such as wind speed and direction, water speed and depth. Owing to inherent time-variety and uncertainty associated with these various factors, it is very difficult to determine optimal sailing speeds accurately for different legs of the whole route using traditional static optimization methods, especially when the weather conditions change frequently over the length of a ship route. Therefore, in this paper, a novel dynamic optimization method adopting the model predictive control (MPC) strategy is proposed to optimize ship energy efficiency accounting for these time-varying environmental factors. Firstly, the dynamic optimization model of ship energy efficiency considering time-varying environmental factors and the nonlinear system model of ship energy efficiency are established. On this basis, the control algorithm and controller for the dynamic optimization of ship energy efficiency (DOSEE) are designed. Finally, a case study is carried out to demonstrate the validity of this optimization method. The results indicate that the optimal sailing speeds at different time steps could be determined through the dynamic optimization method. This method can improve ship energy efficiency and reduce CO₂ emissions effectively.     

Impacts of plug-in electric vehicles in the portuguese electrical grid

Powertrain electrification is currently the best alternative to ensure sustainable energy efficient personal mobility, increasing the integration of intermittent Renewable Energy Sources (RES), improving air quality in urban centres, and reducing greenhouse gas emissions from the transport sector and their dependence on fossil energy sources. With the increasing number of Electric Vehicles (EVs) available from automotive manufacturers, one key question that arises is the capability of the electrical grid to feed the increasing energy demand of the EV fleet without major investments. This paper shows that a progressive penetration of EVs, even at a rapid rate, is perfectly possible for vehicles that offer autonomy, energy consumption and charging characteristics that are currently available in the market. This analysis is based on data acquired during a year, using a Plug-in Hybrid Electric Vehicle (PEV) as the only vehicle for a typical, Southern European Portuguese family. The energy consumption of a gasoline and electric vehicle is presented, as well as its impact on the household load pattern. An analysis of the impact on the grid is also presented, considering several penetration rates (100 thousand, 500 thousand and 1 million vehicles). As well as the avoided use of fossil fuel per vehicle and consequent reduction in overall emissions when compared with a conventional vehicle.     

Energy use in passenger transport in OECD countries: Changes since 1970

This paper analyzes some of the changes that took place in the structure of energy use for passenger travel in industrialized countries. Data is presented on energy use and travel activity for the four major modes of travel — automobile, bus, rail and air — for eight OECD countries: the United States, Japan, the United Kingdom, West Germany, France, Italy, Sweden, and Norway. We use the Laspeyres and Divisia indices to analyze the causes of the change in energy use between 1970 and 1987. The total change in energy use for travel is explained by changes in domestic passenger transport volumes, the mix of modes of travel, and the energy intensities of each mode. We have found two important effects that have a fundamental impact on energy use for travel since 1970. First, shifts among modes of transport towards more energy-intensive ones and large increases in volumes of travel (measured in passenger-kilometers) increased energy use for travel in many OECD countries, often more rapidly than the overall growth in GDP. Second, energy intensities, measured in mJ/passenger-kilometer, of passenger transport fell only in a few countries between 1970 and 1987. Even though individual automobiles have become more energy-efficient, greater size, power, and weight, worsening traffic conditions in Japan and Europe, and fewer people in cars restrained or even offset efficiency improvements. Particularly notable are the increases in intensities in Japan and Germany. The most important exception to this trend was the United States, but the intensities of land-based travel remain higher there than in most other countries. These findings lead to a pessimistic outlook for future energy use for travel. After all, if little or no energy was saved during the decades of high fuel prices, what can be expected in the 1990s?     

地铁电动车辆电能的测量与分析

介绍了北京地铁在电动车辆上装电子电能表进行电能测量的情况，并对地铁电动车辆电耗统计的数据进行了分析比较，解决了北京地铁车辆耗电无准确测量手段的问题，根据技术的发展，提出了已有地铁车辆不必全装电子能表，而新型地铁车辆可装设电能计算装置的意见。     

维纶纤维砼的抗弯性能实验研究

用干式喷射工艺制成维轮纤砼板，再用金刚石锯将其锯成４ｃｍ＊４ｃｍ＊１６ｃｍ的小试块，对试块进行弯实验，观察到纤维的加入将大幅度地提高高砼的吸收能量的能力，但纤维的加入也产生了数倍至十倍于纤维体积的孔隙。