城市机动车污染物排放总量调查

利用先进的GPS技术调查了宁波市不同道路汽车行驶工况,分析了城市机动车排放污染的状况及影响因素,重点讨论了机动车车型和汽车城市道路运行工况对机动车排放污染物的影响。对宁波市主要道路机动车流量进行了连续12h测量,并根据行驶工况和流量调查估算了宁波城市道路污染物排放总量。     

精调化油器+尾气后处理解决摩托车国3排放问题

化油器精度直接影响尾气中有害气体成分的含量.调解并控制化油器,使发动机在各种工况范围内均能满足适当的富燃(λ＜1),进而提高化油器摩托车的排放特性,并结合三元催化 二次补气的后处理措施,最终使摩托车排放达到国家第3阶段标准限值要求.     

基于遗传神经网络废气分析的汽车故障诊断方法研究

设计了神经网络诊断系统,并用于融合分析废气含量、发动机转速、氧传感器信号及某些工作状态信息诊断汽车故障.设计方法为应用遗传算法的复制、交换、变异过程代替BP网络的反向传播过程,并对遗传算法进行改进研究.实践证明,这种基于遗传神经网络方法的故障诊断系统具有收敛速度快、推广性能强的特点,提高了汽车故障诊断系统的效率和准确性.     

满足摩托车欧Ⅲ排放的催化控制技术

从摩托车欧Ⅲ排放标准、满足欧Ⅲ标准所需的金属载体技术、催化剂技术、催化转化系统匹配技术、催化剂性能评价方法和设备以及载体和催化剂的生产等各方面介绍满足摩托车欧Ⅲ排放的催化控制技术。提出可以使摩托车在15000km耐久后仍能很好地满足欧Ⅲ排放标准的系统技术。     

轻型汽车CO2排放测量不确定度评定

CO₂排放是汽车污染物排放检测的一项重要技术指标,它表征的是汽车排出污染物的多少和车辆能耗高低的参考标准之一,用以控制汽车使用中产生的污染物排放量,避免对环境产生损害。按照GB 18352.6-2016《轻型汽车污染物排放限值及测量方法(中国第六阶段)》的规定使用全球统一的轻型车测试循环工况进行常温下冷启动后污染物排放试验,并对测量结果进行不确定度评定。文章阐述了轻型汽油车CO₂排放测试所用的测试原理、法规工况曲线、测试设备、数学模型等,通过分析影响试验结果的各因素来源,综合计算得出轻型车CO₂排放测试结果的扩展不确定度和相对扩展不确定度。     

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.     

我国摩托车燃油蒸发排放国家标准GB 20998-2007的制定与研究(1)

在研究制定我国摩托车燃油蒸发排放标准时,不仅要考虑我国摩托车工业的现状,还要最大限度地与国际排放法规接轨.由于燃油蒸发排放标准在我国是首次制定,并且加装摩托车燃油蒸发排放控制装置后,会对摩托车原来的起动性能、怠速性能、尾气排放等产生一定影响,建议摩托车生产企业在技术上积极应对,做好匹配工作,生产满足国家标准要求的产品.     

催化转化器失效的研究

简要介绍了催化器的结构组成和工作原理，重点论述了三效催化转化器的失活机理，由于长期处于高温状况下工作造成的热失效和燃料中的S、Pb、Mn及润滑油中的Zn和P等造成的催化器的化学中毒，详细介绍了热中毒和化学中毒对催化器性能的影响。最后文章介绍了几种现场评价催化器失效的简单方法和对催化器进行定性、定量分析的理化分析方法，对催化器进行全面具体的分析。     

柴油机电控技术发展与国Ⅲ排放技术路线

介绍了国外各种柴油机电控燃油喷射技术的发展历程、系统典型代表及各阶段的技术特点,阐述了我国应达到国Ⅲ排放标准的技术措施及所采用的电控和非电控燃油喷射技术的特点,指出目前我国采用的电控分配泵、电控泵喷嘴、电控组合单体泵、高压共轨及电控直列泵＋冷却EGR等柴油机燃油喷射技术路线可以满足国Ⅲ排放法规的要求。     

Methods of analysis for vehicle soak time data

Vehicle soak time, the duration of time a vehicle’s engine is at rest prior to being started, and its distribution function are important transportation activity data inputs for mobile emissions inventory estimation due to their impacts on vehicle start and evaporative emissions. This paper provides vehicle emission researchers with an overview of statistical analysis methods relevant to analyzing vehicle soak time data. Many of these methods are already in use in emissions research and have appeared in the literature. These methods are reviewed and further details regarding the implementation and interpretation of these methods are provided. Statistical methods relevant to the analysis of soak time data that have yet to appear in the emissions literature, including kernel density estimation and generalized linear models, are also introduced. Advantages and disadvantages of the methods are compared and theoretical justification is provided. Issues of correlated observations and censored data are discussed. General guidelines for the analysis of soak time data, such as stratification by start type and geographical region, are established. Finally, a subset of the statistical methods discussed is used to analyze the US Environmental Protection Agency’s 3-city data.