CLY6798CNG压缩天然气城市客车开发

介绍CLY6798CNG压缩天然气城市客车的车身结构特点和技术参数等。     

Scavenging a sub-chamber type CNG fueled engine

The sub-chamber type gasoline engine was suggested to be a type of clean engine, but the presence of residual gas in the sub-chamber was a serious fault. In this experimental study, the CNG direct injection method was applied to scavenge residual gas from the sub-chamber. The CVC (constant volume chamber) is divided into the sub-chamber and main-chamber and used as the main experimental apparatus. Because each combustion chamber of the CVC has an injector, the injector can be used freely, at the same time or individually. Therefore, the scavenging efficiency can be improved by changing injection times for the sub-chamber. The experimental results demonstrated that when all the fuel was injected into the sub-chamber, the combustion duration was shortened by 30% compared to that of injection into the main-chamber. Although residual gas was observed in the CVC, when the frequency of injections into the sub-chamber increased, good combustion characteristics were obtained.     

轻型CNG车颗粒物排放特性研究

对同一台轻型两用燃料（C N G和汽油）车使用同一批次基准天然气和基准汽油,在底盘测功机上进行NEDC ,FTP75和WLTC循环对比试验,使用CVS定容取样系统和ELPI设备分析颗粒物等排放。研究发现：3种循环中,试验车辆燃用CNG和汽油,排放颗粒物在 Dp ＝40 nm和 Dp ＝330 nm附近均出现峰值,Dp ＝40 nm处汽油峰值远高于CNG ,Dp ＝330 nm处CNG峰值略高于汽油;CNG的PN和PM的排放率随车速的升高而增大,在较低的匀速工况下增长幅度较小,高速工况下增长幅度较大;CNG在NEDC循环中排放的核态和聚集态颗粒物各占50％左右,FTP75和WLTC循环中排放的聚集态颗粒物占比高于NEDC ;CNG在NEDC循环中单位里程颗粒数和颗粒总数最多,FTP75和WLTC循环中单位里程颗粒数基本相同;WLTC循环中排放的颗粒物质量总量最多,FTP75和NEDC循环中排放的颗粒物质量总量基本相同;FTP75和WLTC循环中单位里程排放的颗粒物质量基本相同,约为N EDC循环的2倍。     

增压柴油/CNG双燃料发动机CNG电控技术研究

介绍了一套自主开发研制的CNG电控喷射系统，并利用该系统将一台D6114增压柴油机改装成了柴油／CNG双燃料发动机．台架试验表明：相对于原型机，改装后的双燃料发动机碳姻的排放量下降50％以上，常用工况柴油替代率超过50％，燃料成本下降20％以上．     

天然气压缩着火燃烧过程的研究

介绍了对压燃式天然气(CNG)发动机进行的研究。研究了不同的涡流室形状及通道直径和进气温度及CNG供气时刻对该发动机动力性的影响,并对CO,THC,NOx的排放进行了分析,探索了CNG发动机实现压缩着火的途径,为今后的继续研究做了技术上的准备。     

H_∞鲁棒控制理论应用于CNG发动机怠速控制

针对CNG发动机的不确定性,将H∞鲁棒控制理论应用于CNG发动机的怠速控制,阐述了H∞加权混合灵敏度设计问题模型,建立了CNG发动机动力学模型,分析了发动机的不确定性.应用Matlab鲁棒控制工具箱,设计出基于H∞理论的CNG发动机的怠速控制器,并进行了仿真分析和试验.结果表明,H∞控制具有很好的鲁棒性,提高了CNG发动机怠速工况的稳定性.     

某天然气发动机示功图测量方法研究

对某天然气发动机缸内压力信号、齿盘脉冲信号和上止点脉冲信号进行同步采样。采用磁电法和气缸压缩线法确定了上止点;利用缸内压力、上止点脉冲和齿盘脉冲同步采样信号,采用上止点基准法和本研究提出的磁电插值法来确定曲轴转角,获取p-φ图并对这两种方法进行了对比研究。     

Cost benefit analysis of three different urban bus drive systems using real driving data

One of the CIVITAS-ELAN project measures in Ljubljana, Slovenia, was the introduction of alternative city bus propulsion systems (CNG, hydraulic hybrid buses) into the public transport and comparison of their performance in terms of costs and benefits with conventional (diesel) buses. A cost-benefit analysis was conducted to provide a model for identifying the most attractive alternative, with aim of aiding the decision making process for future rational up-scaling of the alternative propulsion technologies in PT fleet in Ljubljana. This paper focuses on presenting the key findings of this CBA, using real driving data, while demonstrating the sensitivity/variance of different parameters of a CBA, as well as the differentiation between uncertainties of parameters in an ex-ante analysis versus an ex-post analysis.     

东风系列电控CNG喷射发动机的开发

面对国家能源安全和环保政策的要求,简单阐述了东风汽车公司CNG发动机开发战略,介绍了东风CNG发动机的主要技术特点和参数,概述了东风CNG发动机的设计和标定工作,最后简单介绍了东风CNG发动机的应用与发展。     

压缩天然气气瓶检测管理系统的设计*

针对CNG气瓶的使用现状，经过分析CNG气瓶检测的工艺流程，选用 MVC框架对气瓶检测管理系统的总体框架进行了设计，提出了基于B/S架构的系统界面设计和软件开发环境需求，完整的设计了气瓶检测管理系统的自动化方案。通过建立基于 Web的车载气瓶检测信息管理系统，实现对气瓶检测整个过程的统一管理。