Research On Assessment Of The Blocking Condition In The Three-way Catalytic Converter

Three-way catalytic converter plays an important role in the exhaust system. It influences the pollutant conversion rate, while it has a great impact on operating efficiency of the engine.If the catalytic converter is blocked, the efficiency of the vehicle will decrease and the travel costs will increase. The engine working under high backpressure conditions will generate a lot of heat, so that the engine failure, while emissions of excessive harmful gases will pollute the environment. In these situations, we need to replace the catalytic converters timely based on its operating conditions.Therefore, this paper presents a new assessment methods of catalytic converter blocking condition based on image processing technology.In this thesis, a new evaluation method of catalytic converter blocking condition by image processing technology was proposed based on the review of domestic and foreign papers. The basic concepts of the catalytic converter is introduced and the reason of failure in catalytic converter is analyzed. A platform is designed to acquire reliable image of end surface of catalytic converter. The image is transformed into binary image after the image pre-processing. The area of catalytic converter is abstracted by binary image expansion, corrosion, opening operation, closing operation and other treatment. The algorithm in this study is validated by processing of catalytic converter partial image and provides the basis for practical application. The passing rate and the blocking ratio of the catalytic converter are calculated and the calculation results correspond with the actual. The flow distribution in the catalytic converter is analyzed. The three-dimensional model is established and is meshed. The meshed model is simulated to get the distribution characteristic in ideal condition. Different models are simulated and the results shows that the bigger the blocking ratio is, the more the velocity of the gas in catalytic converter and the pressure in inlet pipe increase. The effect of blocking ration on vehicles is determined.The research results not only provide support for quantization of blocking condition of catalytic converter and the influence of blocking condition on vehicle dynamics and emissions, but also presents a new idea for the quantitative detection of catalytic converters.