论文部分内容阅读
柴油发动机的排放与Blue-Tec发动机汽车的发明,方便了人们的出行,缩短了城市之间的距离。而商用车的诞生和发展弥补了航空与铁路的不足,实现了点对点的运输,使货物的运输及时和准确,但是也随之带来了交通拥挤和尾气污染。汽车尾气污染已经成为破坏生态环境的主要原因之一(见图33)。各国政府根据当地汽车发展的情况分别制定了相应的车辆排放标准。我国也制定了相关方面的法规政策,而北京等大城市商用车已经率先开始实行欧Ⅲ排放标准(见图34、35)。商用车由于工作条件的不同,通常需要动力强劲的柴油发动机,而早期的柴油发动机由于受技术水平的限制,其排放水平较低。而柴油发动机排放级别的改变,在很大程度上取决于发动机的喷射系统。早期的柴油发动机使用直列泵,如A型泵、M型泵、P型泵和美国的卢卡斯直列泵等。20世纪80年代末,卡车生产企业开始与发动机厂家合作,将发动机凸轮轴的
Diesel engine emissions and Blue-Tec engine car invention, convenient for people to travel, shorten the distance between cities. The birth and development of commercial vehicles make up the shortcomings of aviation and railways, and realize the point-to-point transportation so that the transportation of goods is timely and accurate, but it also brings traffic congestion and tail gas pollution. Vehicle exhaust pollution has become one of the main causes of ecological damage (see Figure 33). According to the development of local automobiles, governments of all countries have formulated corresponding vehicle emission standards. China has also formulated relevant laws and policies, while commercial vehicles in major cities such as Beijing have taken the lead in implementing Euro III emission standards (see Figures 34 and 35). Commercial vehicles usually require a very powerful diesel engine due to different working conditions, whereas earlier diesel engines were less advanced due to technical limitations. The change in diesel engine emission levels, to a large extent, depends on the engine’s injection system. Early diesel engines use in-line pumps, such as A-type pumps, M-type pumps, P-type pumps and Lucas in the United States and other pumps. The late 1980s, truck manufacturers began to work with engine manufacturers, the engine camshaft