混合动力轿车性能的测试研究

介绍了本田Insight混合动力电动轿车在实际道路和汽车转鼓试验台上按照国家标准和欧洲的一系列工况循环下测得的动力性、平均燃油消耗和排放的试验结果。在模拟真实环境的循环下,除了NOx的排放外,Insight的性能明显地优于传统汽油轿车的性能。     

沥青混合料低温抗裂性能研究

以低温弯曲试验为基础,得出沥青混合料破坏能的函数关系。采用Burgers模型作为本构模型,对低温弯曲蠕变试验结果进行非线性分析,得出材料模型的粘弹性参数。通过模拟路面降温条件,采用粘弹性方法以Burgers模型为基础得出温度应力的计算公式,以及温度应力产生的应变能的计算方法,进而以能量为判据,提出将温度应力产生的应变能与沥青混合料的破坏能相比较,从而判断沥青路面是否发生低温开裂的预估方法。     

用能量法分析钢桥面沥青混合料铺装体系疲劳特性

介绍了沥青混合料的滞后回路方程和能耗分析方法,并用能量法分析了钢桥面沥青混合料铺装体系疲劳特性, 提出了疲劳寿命预测公式。通过南京长江第二大桥钢桥面铺装体系疲劳试验结果的实例分析,表明能量法可用于分析钢桥面沥青混合料铺装体系疲劳特性,其疲劳寿命预测结果是较为精确的,而且指出了环氧沥青混凝土铺装具有很好的抗疲劳性能。     

Closed-loop Inventory Routing Problem for returnable transport items

Increasing concerns on supply chain sustainability have given birth to the concept of closed-loop supply chain. Closed-loop supply chains include the return processes besides forward flows to recover the value from the customers or end-users. Vendor Managed Inventory (VMI) systems ensure collaborative relationships between a vendor and a set of customers. In such systems, the vendor takes on the responsibility of product deliveries and inventory management at customers. Product deliveries also include reverse flows of returnable transport items. The execution of the VMI policy requires vendor to deal with a Closed-loop Inventory Routing Problem (CIRP) consisting of its own forward and backward routing decisions, and inventory decisions of customers. In CIRP literature, traditional assumptions of disregarding reverse logistic operations, knowing beforehand distribution costs between nodes and customers demand, and managing single product restrict the usage of the proposed models in current food logistics systems. From this point of view, the aim of this research is to enhance the traditional models for the CIRP to make them more useful for the decision makers in closed-loop supply chains. Therefore, we propose a probabilistic mixed-integer linear programming model for the CIRP that accounts for forward and reverse logistics operations, explicit fuel consumption, demand uncertainty and multiple products. A case study on the distribution operations of a soft drink company shows the applicability of the model to a real-life problem. The results suggest that the proposed model can achieve significant savings in total cost and thus offers better support to decision makers.     

宜万铁路齐岳山隧道629高压充水溶腔处理技术

在齐岳山隧道正洞DK363+629掌子面进行超前水平钻探时,揭示出前方存在一个大型腔体,随后实施超前探测,初步判断了腔体形状,对腔体进行了处理。首先对溶腔进行注浆试验,总计注浆1 613 m3,注浆效果不明显,掌子面停止注浆试验;注浆试验失败后,对DK363+629溶腔进行放水试验,放水量为3 000 m3/h,持续放水共计144 h,水量约43万m3,水压持续在0.2 MPa左右,由于受到外界降雨的影响水压持续上扬,证明腔体具有良好的地表联通性和水量补给持续性,为了保证施工安全停止了放水试验。平导贯通后可采用自然流出法排水,并对腔体采取"释能降压"施工。本次泄水总量约63万m3,水压自0.4 MPa降至0.0 MPa,水量稳定在约1 000 m3/h;随后对腔体实施爆破施工,爆破后采用管道引排的方法在不改变原有水流方向和不影响整体地下水系的情况下顺利通过。     

CO2 efficiency in road freight transportation: Status quo, measures and potential

Road freight transport continues to grow in Germany and generates 6% of the country’s CO₂ emissions. In logistics, many decisions influence the energy efficiency of trucks, but causalities are not well understood. Little work has been done on quantifying the potential for further CO₂ reduction and the effect of specific activities, such as introducing computer assisted scheduling systems to trucking firms. A survey was survey out and linked fuel consumption to transport performance parameters in 50 German haulage companies during 2003. Emission efficiency ranged from 0.8 tonne-km to 26 tonne-km for 1 kg CO₂ emissions. The results show potential for improvements given a low level of vehicle usage and load factor levels, scarce use of lightweight vehicle design, poorly selected vehicles and a high proportion of empty runs. IT-based scheduling systems with telematic application for data communication, positioning and navigation show positive effects on efficiency. Fuel use and transport performance was measured before and after the introduction of these systems.     

滑行回馈强度对整车能耗的影响

能量回馈可以有效提高新能源汽车的续航里程,文章以某款纯电动车的滑行回馈能量回收系统为研究对象,在世界轻型汽车测试循环（WLTC）工况下,测量不同回馈强度下整车的续航里程,分析滑行回馈强度对整车能耗的影响。实验结果表明,随着滑行回馈强度的增大,整车能耗先逐渐减低,当滑行回馈强度增大至一定程度之后,能耗不再减低,反而随着滑行回馈强度的增大而增加。     

汽车气囊式行人保护装置设计

交通事故特别是人车碰撞事故造成的人员伤亡巨大。为提高汽车被动安全性,设计了汽车气囊式行人保护装置,分别对行人头部与汽车前挡风玻璃、外置安全气囊进行碰撞仿真分析,结果表明,无气囊条件下头部头部损伤指标（HIC）为 2 123,有气囊条件下 HIC 值为845,因此,汽车气囊式行人保护装置能够有效降低行人头部伤害。使用 AD 软件设计了汽车气囊式行人保护装置硬件电路,同时使用 Proteus 结合 Keil 进行电路仿真,通过仿真验证了安全气囊能够在特定条件下成功触发。     

基于整车能量流分析的 WLTC 循环油耗优化

文章基于一辆搭载增压发动机的整车进行轻型汽车测试循环的能量流试验,确定整车 能量利用与损耗的分布,分析损耗原因及潜在优化方向。应用 GT-Suite 软件平台搭建整车系统仿真模型,用能量流测试数据对模型进行校核,优化能耗,降低世界新型车测试循环油耗。依据仿真优化方案对实车整改,验证节油效果。结果表明,通过优化标定策略、改善冷却水 路与油路循环和优化起燃过程能够降低未燃化学能损失、换热损失和排气能量损失,使轻型汽车测试循环油耗降低了 3.68%。此外,还使发动机冷却水温达到平衡温度的时间缩短了 73 s, 且变速器油温显著升高。     

中国汽车能耗现状及未来趋势

基于环保和可持续发展要求,各国对汽车的能耗都有强制且清晰的要求,如何降低能 耗是当前各大车企的主要研究课题之一。文章在研究相关资料的基础上,结合当前汽车发展 已有技术对目前市场上的汽车减排技术进行了分析与整理,主要介绍当前市场上主流的五种 节能减排方式：车身轻量化、提升发动机热效率、采取发动机混动技术、开发能量回收系统和低风阻系数。汽车降耗技术的开发需要不同车企协同合作,任何企业不能独立钻研某一技术,需要对不同技术进行共时性探索。目前我国汽车自有品牌正在积极探索相关技术,未来 必将拉动中国汽车产业技术革新和经济增长。