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在80年代中期人们做了大量的使重型柴油机能够满足颗粒排放限制标准的开发工作。这些限制值尽管以今天的标准来看是高了,但在当时却认为具有很大的约束性。一些制造厂为了达到0.6g/制动马力-小时的颗粒限制标准以便给生产的可变性留有足够的余量以及为了解决因之造成的产品性能降低曾进行了不懈的努力。通过改变发动机和燃油系统的设计,使得柴油机的废气排放控制取得了重大进展。这使得在1991年便能达到0.45g/制动马力-小时的颗粒排放水平。重型柴油机下一步的颗粒排放指标是到1994年达到0.1g/制动马力-小时。为迎接这一挑战,发动机开发者们不但要考虑发动机及喷油来统的设计变革,而且还要考虑燃油的改进以及废气的再处理。本文对过去的和目前的用于现代柴油机废气排放控制的各种策略作了回顾。
In the mid-1980s, a great deal of development was done to enable heavy-duty diesel engines to meet particulate emission limits. These limits, while high by today’s standards, were considered binding at the time. Some manufacturers have made unremitting efforts to achieve a particle size limit of 0.6 g / brake horsepower-hour to allow sufficient margin for variability in production and to address the resulting reduction in product performance. Significant progress has been made in the control of emissions from diesel engines by changing the design of the engine and fuel system. This enabled a level of particulate emissions of 0.45 g / hp-hr in 1991. The next major particle emission target for heavy-duty diesel engines is 0.1 g / hp-h in 1994. To meet this challenge, engine developers must consider not only engine and fuel injection design changes, but also fuel improvements and exhaust gas reprocessing. This article reviews past and current strategies for controlling exhaust emissions from modern diesel engines.