Study On Deteriorating Characteristic Analysis On Three-way Catalytic Convener Used In The Car And Its Servce Life Forecasting

The automobile exhaust accounted for about50%of air pollution poses a gravethreat to human environment. Therefore, it is extremely urgent to develop purificationtechnology for automobile exhaust, in which three-way catalytic convener is the mostimportant purification technology outside the machine. However, three-way catalyticconverter often deteriorates because of the long-term working in a severe conditionand its conversion efficiency drops at the same time. Therefore, it is absolutelyimportant to study the characteristic of deterioration for three-way catalytic converter.So，this paper research on reaction mechanism of Vehicle emission Three WayCatalyst and its life prediction and performance deterioration based on Hunan keyscientific and technological project《The research and development of Motor Vehicleemission Three Way Catalyst》and Hunan technology project 《The development andapplication of Vehicle emission Three Way Catalyst efficient technology with lowpollution and long life》. The following are the main contents and innovations of thispaper:Firstly, this article not only describes deteriorating mechanism of three-waycatalytic converter but also creates the deteriorating characteristic model combineddeteriorating mechanism and chemical reaction by considering Pt particles averagediameter and response frequency factor, second, validity of the model was verified bycomparing results of simulation experimental about NO and CO.Secondly, Based on the model, numerical simulation of temperature and oxygenfields was simulated using CFD software, the relational graph of road haul wasexported by leading case and data to processing software after defining function of Ptparticles average diameter and response frequency factor, its main deterioratingcharacteristics of three-way catalytic convener are Pt particles average diameter andresponse frequency factor. According above-named causes, some measures werebrought to prevent the deterioration of Pt particles average diameter and responsefrequency factor.Finally, based on the theory of grey correlation and univariate analysis, theimpacts of inlet temperature, road haul and divergence angle deterioratingcharacteristics of three-way catalytic converter was studied, and a prediction model oflifetime about the three-way catalytic convener was established according to GM (1,1) model of grey theory at the same time. This supplied certain foundation for thestructure optimization and performance improvement of three-way catalyticconverter.