| Nowadays air pollution problem in big cities of China is becoming increasingly severe. Harmful exhaust emission from vehicles is one of the main factors. To limit diesel engine's emission, all kinds of technologies, especially diesel after-treatment technology, are booming world-widely. In this circumstance, automotive department of Wuhan University of Technology and test institute of China Automotive Technology and Research Center take the project, "diesel oxidation catalyst and its fast aging", a 863 item sponsored by China's Science and Technology Department. The object of this program is to seek fast aging regulation that is appropriate for our country. Analyzing diesel oxidation catalyst aging mechanism, working out a testing cycle of fast aging that should satisfy Chinese diesel-powered vehicle features and the transportation status and establishing corresponding test equipment are main tasks of this dissertation.Emission producing mechanism of diesel emission and the impacts on human and environment caused by these substances are discussed firstly, drawing a conclusion that particulate and NOX are the key of diesel emission control and developing a basic knowledge on emission regulations and testing technologies. A few after-treatment technologies of diesel engine are summarized and a simple evaluation system is created. However, this dissertation mainly focuses on diesel catalyst aging mechanism including heat deterioration and performance degradation caused by toxic substance. Following the above conclusions, a fast aging test cycle is produced which consists of three stages. A single cycle is one hour, and there are totally 100 cycles, namely 100 hours. The whole aging cycle is equal to 100,000 kilometers road aging. 200℃ and 400℃ catalyst entrance temperature can be obtained by the adjustment of engine speed and load, while 600℃ obtained by fuel injection and combustion. In the last chapter, the paper designs a simple setting of fast aging test system.
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