Simulation And Grey Performance Degradation Of Cerium-Based Catalytic Particulate Trap Forecasting Research

The "Dual-Carbon" strategy advocates a green,environmentally friendly and low-carbon mode of transportation.However,as the number of vehicles increases year by year,the emission of carbon dioxide and other harmful substances in vehicle exhaust will further aggravate the environmental pollution.And the solution of the control problem needs to be solved urgently.Cerium-based catalytic particulate filter is widely used as a device that can effectively reduce particulate matter and harmful gases in diesel exhaust emissions,but its core component,the porous media filter,is prone to deterioration and thermal shock in the environment of high temperature and thermal shock.Problems such as failure lead to the further development and application space of catalytic particulate traps being hindered.Based on the National Natural Science Foundation of China project "Research on the Deterioration Mechanism and Synergy of Diesel Engine Exhaust Purification System Coated with Graphene/Metal Catalyst"(51976016),the paper adopts numerical model simulation analysis and experiment,and combines the gray algorithm to investigate the cerium-based catalyst.The performance degradation simulation and grey prediction research of the cerium-based catalytic particulate trap were carried out to achieve the purpose of multi-dimensional analysis of the degradation of the cerium-based catalytic particulate trap.The main research work of this paper is as follows:(1)Combined with the structural characteristics of the catalytic particulate trap and the required research content,the plug flow single-channel reaction kinetic model of the catalytic particulate trap is established,and the process of catalytic regeneration is numerically simulated and analyzed.Validation of the model was confirmed by completing experimental validation using a thermogravimetric analyzer.(2)The regeneration performance of cerium-based catalytic particulate trap under the influence of regeneration control temperature,NOx input concentration and SO2 concentration was analyzed.The results show that the cerium-based catalyst can greatly reduce the initial temperature of soot regeneration and the NOx reduction rate.At the same time,with the increase of temperature,the soot regeneration rate and NOx reduction rate both increase first and then decrease.The increase of the ratio a of NO2 in NOx and the ratio of NOx mass to soot particle massβ will lead to a decrease in the NOx reduction rate and an increase in the soot regeneration rate.Increasing the value of a will lead to an increase in the critical temperature of catalyst failure,while increasing the value of β will lead to a decrease in the critical temperature of catalyst failure.There is a certain equilibrium relationship between N2O and the actual catalyst poisoning.Higher temperature will inhibit the formation of N2O,but increase the possibility of catalyst failure.The NOx reduction rate and the soot regeneration rate decreased with the increase of SO2 concentration.On the contrary,the catalyst failure temperature increases with the increase of SO2 concentration.(3)Using orthogonal experimental design(OED,Orthogonal experimental design)and fuzzy grey relational analysis(FGRA,Fuzzy grey relational analysis)to evaluate and analyze the factors affecting the performance degradation of cerium-based catalytic particulate traps in detail,From the data analysis conclusion,it can be seen that the six major operating parameters(regeneration temperature,NOx amount,catalyst coating amount,SO2 concentration,oxygen concentration,exhaust flow rate)are the main factors affecting the performance degradation of the cerium-based catalytic particulate trap.The amount of NOx has the most significant effect on the maximum wall temperature.(4)Through the thermal aging experiment of cerium-based catalyst and the prediction of grey model GM(1,1),it is concluded that the catalyst activity reaches the highest at 592℃,and then the activity of the catalyst decreases with the increase of temperature.The catalyst basically fails when the temperature reaches 800℃.And through the GM(1,1)model prediction,the average relative error between the experimental data and the predicted data is 4.665%,and the accuracy level is second-level,which proves that the thermal aging prediction of the catalyst can be carried out by the GM(1,1)model.On the one hand,the research content of this paper provides a theoretical basis for the redox reaction process,the prediction of the concentration change of reaction components and the prediction of the influence of temperature change in the color process catalyzed by the cerium-based catalytic particulate trap;The performance optimization of particle trap provides reference and ideas.