| Among the numerous regeneration methods of particulate filter,soot regeneration of passive regeneration technology under the heavy load is a regeneration method without additional facilities.There are still many unsolved technical difficulties in the research of soot continuous regeneration,especially the simulation research field.Considering the characteristics of the actual exhaust pressure change of the diesel engine(nonlinear and periodic),the soot regeneration under the periodic fluctuating intake pressure mode is defined as the soot continuous pulsation regeneration.In this study,the flow field,heat transfer performance,combustion characteristic and reaction mechanism of the soot continuous regeneration process of the particulate filter are studied.The research results can improve the regeneration performance of the particulate filter system which has theoretical and practical significance.Based on the National Natural Science Foundation of China [51676066] "Pd /graphene catalytic rotary particulate f ilter regeneration and thermal electro chemical mechanical coupling collaborative optimization research".The soot continuous pulsation regeneration performance of diesel particulate filter under different conditions was studied and analyzed by using the method of model development,numerical simulation and experimental verifica tion.The factors affecting the continuous pulsation regeneration of the particle filter are determined.The main innovations of this paper are as follows.(1)The trend of soot regeneration pressure and the change of pressure drop inside the particulate filter were investigated.A continuous pulsation regeneration model of nonlinear regeneration pressure fluctuation was established and studied.Through the calibration of clean particle filter pressure,the pressure correction of soot deposition process and the validation of regeneration process compared with the experiment and simulation result of the references,the particle filter under variable flow condition was studied by changing the parameters such as pore density,pore wall thickness and permeability.The response time and pressure drop of soot deposition were measured.The simulation results under variable flow co nditions show that the key parameters affecting the overall pressure drop change of the particle filter are pore density and pore wall thickness and permeability are non-key parameters.(2)The influence of inlet pressure on the performance of continuous p ulsating regeneration was investigated.The flow field,heat transfer performance and regeneration efficiency of the soot regeneration part iculate filter system under the condition of sine and cosine inlet pressure were studied.Compared with the results o f cosine inlet pressure,the system temperature,Reynolds number and pressure drop at sinusoidal inlet pressure are lower of 46.12 K,435.23 and 4353.5 Pa,respectively.The results show that the distribution trend of heat transfer on the wall with sinusoi dal inlet pressure is consistent.The sinusoidal inlet pressure is more conducive to the continuous pulsation regeneration of soot.(3)The models of Effective Definition Calibration Rate(EDC),Forbid Rate(FR)Effective Definition Rate(ED)were compared.The thermal effect data of soot regeneration performance,dynamic characteristics,pressure and combustion reaction were analyzed.3 models can realize continuous pulsation regeneration of soot with the regeneration efficiency above 88%.EDC model has higher turbulent kinetic energy(48.75 J larger than FR model and 49.01 J larger than ED model)and lower Reynolds number.The temperature of EDC model is higher than that of ED and FR models.The temperature difference of inlet,filter body and outlet are 265.4 K,24.7 K and 8.4 K,respectively.(4)The effects of oxygen concentration and regenera tion temperature on the continuous pulsation regeneration characteristics of the particle filter were investigated.9 simulation conditions were set,including 823 K,873 K and 923 K of regeneration temperature,7.2%,8.2% and 9.4% of oxygen concentration.The results showed that the soot regeneration performance was significantly different under 9conditions and the maximum temperature difference was 286 K.In the process of soot continuous pulsation regeneration,the effect of oxygen concentration on regeneration reaction is much greater than that of regeneration temperature.(5)The performance of microwave-assisted continuous pulsation regeneration based on field synergy theory is studied.The effects of different flow rates and exhaust temperatures on the regeneration temperature field were comprehensively investigated.The temperature uniformity coefficient and field synergy coefficient are used for data analysis and comparison.The average regeneration temperature at the outlet increases with the improvement of exhaust temperature.When the exhaust temperature is 680 K,the maximum temperature of microwave-assisted continuous pulse regeneration is 1021.8 K... |
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