摩托车不锈钢紧固件的热处理

随着摩托车向轻量化、节能化及环保化发展,对摩托车紧固件也提出了轻量化、更高设计应力及更合理坚固技术要求。为减小高强度坚固件氢脆断裂的危险,采用不锈钢和耐热钢制造发动机螺栓是最有效的措施之一。尽管不锈钢材料牌号有很多种,但还需通过正确的热处理工艺手段,才能更好地发挥不锈钢的性能,因此,热处理工艺是提高不锈钢紧固件品质和使用可靠性的重要保证。     

氢燃料电池汽车产业价值链分析

氢燃料电池技术有可能为汽车、能源工业带来革命性的变化,毫无疑问会使汽车产业的竞争格局、能源供应方式发生根本变化。汽车产业价值链将出现重大的变革,价值链的核心不再是燃油、燃油发动机,而是氢燃料电池、储氢与供氢系统。本文建立氢燃料汽车价值链模型并进行了分析,氢燃料汽车电池、储氢与供氢系统将是新商业模式最大受益者;燃油、内燃机供应商、传统汽车制造商的前景将不容乐观,相关企业需从新的产业链找到位置和突破口,才能在变革中求得发展。     

氢气储存方法的现状及发展

氢能是21世纪主要的新能源之一。本文介绍了几种常用的储氢技术如高压压缩储氢技术、液化储氢技术和金属氢化物储氢技术等的研究进展,比较了各种储氢的优缺点,并对规模储氢技术的发展前景进行了预测和展望。     

Environmental life-cycle assessment of transit buses with alternative fuel technology

The paper presents a life-cycle assessment of costs and greenhouse gas emissions for transit buses deploying a hybrid input-output model to compare ultra-low sulfur diesel to hybrid diesel-electric, compressed natural gas, and hydrogen fuel-cell. We estimate the costs of emissions reductions from alternative fuel vehicles over the life cycle and examine the sensitivity of the results to changes in fuel prices, passenger demand, and to technological characteristics influencing performance and emissions. We find that the alternative fuel buses reduce operating costs and emissions, but increase life-cycle costs. The infrastructure requirement to deploy and operate alternative fuel buses is critical in the comparison of life-cycle emissions. Additionally, efficient bus choice is sensitive to passenger demand, but only moderately sensitive to technological characteristics, and that the relative efficiency of compressed natural gas buses is more sensitive to changes in fuel prices than that of the other bus types.     

燃料电池汽车氢源

从直接储氢和间接制氢两方面来阐述燃料电池汽车氢源；重点介绍气态、液态、金属氢化物、纳米碳材料储氢方式以及硼氢化物制氢方式和甲醇或汽油催化重整制氢方式。     

燃料电池发动机氢耗量半经验动态模型

在氢耗量稳态特性模型基础上,通过试验研究,建立了燃料电池发动机氢耗量半经验动态模型,并对模型进行了试验验证。结果表明,该模型能反映燃料电池氢耗量的动态特性,精度较高,而且该模型具有结构简单,模型参数较少等特点,通过较少的试验数据即能获得模型中的参数,便于在车辆动力学仿真研究中应用。     

内燃机掺氢燃烧可行性分析

利用氢和汽油或柴油共同作为燃料,可使汽油或柴油充分燃烧,大幅度节约汽油或柴油,降低排气污染,这在目前是很有意义的。文章综述了掺氢内燃机的研究现状,分析内燃机掺氢燃烧（以汽油机为主）的特性、掺氢燃烧的优势以及掺氢对柴油机过量空气系数的影响,通过内燃机掺氢以后动力性能、经济性能与排放性能的改变,论证了掺氢内燃机的优势及市场的潜力。     

不同EGR对氢内燃机的燃烧特性影响

本文基于fire三维CFD模拟软件,建立单缸进气歧管喷射的氢内燃机三维燃烧模型,重点研究了不同EGR率下,氢内燃机的压力场、温度场以及排放的变化。分析结果表明,随着EGR率的不断提高,氢内燃机的最高压力值、最高温度和压力升高率、温度升高率均下降,NO排放量大幅降低,但同时对动力性和经济性也有一定影响。     

The role of charging and refuelling infrastructure in supporting zero-emission vehicle sales

Widespread uptake of battery electric, plug-in hybrid, and hydrogen fuel-cell vehicles (collectively zero-emissions vehicles or ZEVs) could help many regions achieve deep greenhouse gas mitigation goals. Using the case of Canada, this study investigates the extent to which increasing ZEV charging and refuelling availability may boost ZEV sales relative to other ZEV-supportive policies. We adapt a version of the Respondent-based Preferences and Constraints (REPAC) model using 2017 survey data from 1884 Canadian new vehicle-buyers to simulate the sales impacts of increasing electric vehicle charging access at home, work, public destinations, and on highways, as well as increasing hydrogen refuelling station access. REPAC is built from a stated preference choice model and represents constraints in supply and consumer awareness, as well as dynamics in ZEV policy out to 2030. Results suggest that new ZEV market share from 2020 to 2030 does not substantially benefit from increased infrastructure. Even when electric charging and hydrogen refuelling access are simulated to reach “universally” available levels by 2030, ZEV sales do not rise by more than 1.5 percentage points above the baseline trajectory. On the other hand, REPAC simulates ZEV market share rising as high as 30% by 2030 with strong ZEV-supportive policies, even without the addition of charging or refuelling infrastructure. These findings stem from low consumer valuation of infrastructure found in the stated preference model. Results suggest that achieving ambitious ZEV sale targets requires a comprehensive suite of policies beyond a focus on charging and refueling infrastructure.     

Well-to-wheel costs,primary energy demand,and greenhouse gas emissions for the production and operation of conventional and alternative vehicles

This study provides a comprehensive comparison of well-to-wheel (WTW) energy demand, WTW GHG emissions, and costs for conventional ICE and alternative passenger car powertrains, including full electric, hybrid, and fuel cell powertrains. Vehicle production, operation, maintenance, and disposal are considered, along with a range of hydrogen production processes, electricity mixes, ICE fuels, and battery types. Results are determined based on a reference vehicle, powertrain efficiencies, life cycle inventory data, and cost estimations. Powertrain performance is measured against a gasoline ICE vehicle. Energy carrier and battery production are found to be the largest contributors to WTW energy demand, GHG emissions, and costs; however, electric powertrain performance is highly sensitive to battery specific energy. ICE and full hybrid vehicles using alternative fuels to gasoline, and fuel cell vehicles using natural gas hydrogen production pathways, are the only powertrains which demonstrate reductions in all three evaluation categories simultaneously (i.e., WTW energy demand, emissions, and costs). Overall, however, WTW emission reductions depend more on the energy carrier production pathway than on the powertrain; hence, alternative energy carriers to gasoline for an ICE-based fleet (including hybrids) should be emphasized from a policy perspective in the short-term. This will ease the transition towards a low-emission fleet in Switzerland.