高压共轨喷油器精密偶件的泄漏分析

高压共轨电控喷油系统中，随着燃油喷射压力的大幅度提高，燃油的粘度-压力效应、粘度-温度效应凸显。作者分析了高压共轨喷油器精密偶件中的泄漏问题，得出的结论是：考虑了燃油的粘压效应、粘温效应后实际的泄漏量并不十分严重；如果考虑油液的极化效应、进口起始段的效应以及环形槽的影响，实际泄漏量可能还会减小。     

燃料电池电动车车载甲醇重整器

对目前世界几大汽车公司研制开发的燃料电池电动汽车车载甲醇重整器加以介绍，着重讨论了重整器的设计与重整催化剂的布置。指出，甲醇重整器的效果良好，但重整器出口富氢重整气中CO的含量仍然很高，而较高浓度的CO会使燃料电池电极中毒。因此，从重整器中产生出来的重整气在进入燃料电池以前要进行净化。     

军用半挂汽车列车的现状和发展趋势

介绍了国内外军用半挂汽车列车的发展现状,根据军用半挂汽车列车的运载对象和使用环境,分析了其性能特点、关键技术和发展趋势.     

Performance Evaluation of Hybrid-Drive Buses and Potential Fuel Savings in Brazilian Urban Transit

Transporting more than 55 million passengers per day, buses are the main transit mode in Brazil. Most of these vehicles use diesel oil and this situation causes dependence on oil, extensive greenhouse gas emissions and increasing air pollution in urban areas. In order to improve this situation the options for Brazilian cities include the use of alternative fuels and new propulsion technologies, such as hybrid vehicles. This article proposes a procedure for evaluating the performance of a recently developed Brazilian hybrid-drive technology. A simple procedure is presented to compare hybrid-drive buses with conventional diesel buses in urban operation focusing on fuel economy and the potential for reducing diesel oil consumption through the use of hybrid-drive buses. Field tests carried out by the authors indicate that fuel consumption improvement through the use of hybrid-drive buses would certainly exceed 20%, resulting in lower fuel costs and reduced carbon dioxide (CO₂) emissions.     

地铁站环控系统控制方案的节能对比研究

为明确常见的地铁车站环控系统控制方案的用能表现和节能潜力,为地铁车站节能降碳提供参考和指导,以北京、上海和广州分别作为寒冷、夏热冬冷和夏热冬暖地区的代表性城市,在 TRNSYS 软件中搭建屏蔽门地铁站模型,探究增设自控系统和优化时刻表控制这 2 种优化方案相比于当前常规的时刻表控制方案在站内环境控制、节能潜力、改造成本方面的表现。结果显示,采用 2 种优化方案均可有效提高站内空调控制温度,实现类似的站内温度控制效果。用能方面,相比于当前的时刻表控制方案,增设自控系统可为各气候区地铁站环控系统降低41%～49%的年能耗,优化时刻表控制方案可降低 38%～48%的年能耗。改造成本方面,优化时刻表控制方案仅需要提高管理水平,无需增加设备和系统,而增设自控系统方案的设备成本和后期运维管理成本较高。因此,综合考虑站内环境控制效果、能耗情况和改造成本,建议地铁站采用优化时刻表控制方案进行节能运行优化,以实现节能目标。     

油束空间分布锥角对柴油可控预混压燃燃烧排放影响的试验研究

在柴油可控预混压燃燃烧模式下,进行了油束空间分布锥角及多脉冲参数对排放影响的研究。试验结果表明,在采用155°和125°油束空间分布锥角的两种油嘴时,通过改变多脉冲喷射定时均可控制预混燃烧放热幅度,但对NOx、HC和CO排放的影响不同;在3次和6次多脉冲喷射条件下,采用小分布锥角(125°)油嘴能够增加有效贯穿距离,提高气缸轴线方向的空气利用率,从而在大脉冲喷射定时条件下改善CO排放,并且可减少50%以上的HC排放。     

基于模糊逻辑推理的燃料电池客车再生制动控制策略

以燃料电池客车为研究对象,在分析城市公交客车制动特点的基础上,进行了制动能量回收的分析计算,提出了一种简单实用的再生制动控制策略的模糊化设计方法。道路试验表明,该设计具有明显的节能效果。     

浅谈康明斯柴油机在船上的应用

科学技术在不断向前发展,船用设备也在不停地更新。陆用康明斯柴油机在船上逐渐得到应用,并有推广的趋势。文章结合作者在船实际工作,分析了康明斯柴油机在船上应用的优缺点。     

Fueling for contingencies: The hidden cost of unpredictability in the air transportation system

The aviation community is increasing its attention on the concept of predictability when conducting aviation service quality assessments. Reduced fuel consumption and the related cost is one of the various benefits that could be achieved through improved flight predictability. A lack of predictability may cause airline dispatchers to load more fuel onto aircraft before they depart; the flights would then in turn consume extra fuel just to carry excess fuel loaded. In this study, we employ a large dataset with flight-level fuel loading and consumption information from a major US airline. With these data, we estimate the relationship between the amount of loaded fuel and flight predictability performance using a statistical model. The impact of loaded fuel is translated into fuel consumption and, ultimately, fuel cost and environmental impact for US domestic operations. We find that a one-minute increase in the standard deviation of airborne time leads to a 0.88 min increase in loaded contingency fuel and 1.66 min in loaded contingency and alternate fuel. If there were no unpredictability in the aviation system, captured in our model by eliminating standard deviation in flight time, the reduction in the loaded fuel would between 6.12 and 11.28 min per flight. Given a range of fuel prices, this ultimately would translate into cost savings for US domestic airlines on the order of $120–$452 million per year.     

Vehicle mass as a determinant of fuel consumption and secondary safety performance

One interaction between environmental and safety goals in transport is found within the vehicle fleet where fuel economy and secondary safety performance of individual vehicles impose conflicting requirements on vehicle mass from an individual’s perspective. Fleet characteristics influence the relationship between the environmental and safety outcomes of the fleet; the topic of this paper. Cross-sectional analysis of mass within the British fleet is used to estimate the partial effects of mass on the fuel consumption and secondary safety performance of vehicles. The results confirmed that fuel consumption increases as mass increases and is different for different combinations of fuel and transmission types. Additionally, increasing vehicle mass generally decreases the risk of injury to the driver of a given vehicle in the event of a crash. However, this relationship depends on the characteristics of the vehicle fleet, and in particular, is affected by changes in mass distribution within the fleet. We confirm that there is generally a trade-off in vehicle design between fuel economy and secondary safety performance imposed by mass. Cross-comparison of makes and models by model-specific effects reveal cases where this trade-off exists in other aspects of design. Although it is shown that mass imposes a trade-off in vehicle design between safety and fuel use, this does not necessarily mean that it imposes a trade-off between safety and environmental goals in the vehicle fleet as a whole because the secondary safety performance of a vehicle depends on both its own mass and the mass of the other vehicles with which it collides.