| The power and fuel economy of direct-injection gasoline vehicles are significantly improved compared to conventional gasoline engines,resulting in the widespread adoption of new gasoline vehicles.However,direct-injection technology results in higher fine particle emissions due to its inherent mixture preparation and combustion mechanism.The catalytic gasoline engine particulate filter system is one of the most effective after-treatment technologies for reducing particulate emissions from gasoline vehicles and has attracted significant attention from domestic and international researchers.Currently,research on catalytic particulate filter systems is mainly focused on the purification performance and regeneration performance of single catalytic converters or particulate filters,and there is a lack of in-depth analysis on the regeneration performance of catalytic particulate filter systems.Since each key influencing parameter has different degrees of influence on the regeneration performance of catalytic particulate trap systems,it is essential to investigate the influence of each key influencing parameter on the regeneration performance to enhance the particulate emission control of gasoline engines.During the study of the regeneration performance of catalytic gasoline engine particulate filter systems,it is important to identify the influence of key influencing parameters on the regeneration performance and how to improve the regeneration performance.Therefore,this paper is based on the National Natural Science Foundation of China(52076184),the National Natural Science Foundation of China(51606162),and the Natural Science Foundation of Hunan Province(2017JJ4052).The regeneration performance of the electric heating catalytic gasoline engine particulate filter systems is studied in depth by a combination of numerical simulation and experiment,and the influence of a variety of key influencing parameters on the integrated regeneration performance is explored.The main work is as follows:(1)The numerical calculation model of the dual-carrier catalytic converter for gasoline engines is established.Using numerical simulation method,the effects of key influencing parameters such as exhaust flow rate,exhaust oxygen concentration,exhaust NO concentration,dual-carrier pore density ratio,dual-carrier wall thickness ratio,and dual-carrier length ratio on the conversion performance of the dual-carrier catalytic converter are investigated.(2)The regeneration performance of the electric heating catalytic gasoline engine particulate filter system is studied and the numerical model is established.The regeneration performance of the conventional and electric heating catalytic particulate filter systems is compared and analyzed.The effect of key parameters on the regeneration performance of the electric heating catalytic gasoline engine particulate filter system is investigated.(3)The numerical model of the radial variable pore density catalytic gasoline engine particulate filter system is established and the influence of various key parameters on the regeneration performance of the catalytic particulate filter system is investigated by using numerical simulation.(4)Orthogonal test method is used to comprehensively explore the comprehensive influence of multiple key influencing factors on the regeneration performance of the electric heating catalytic gasoline engine particulate filter system and the radial variable pore density catalytic gasoline engine particulate filter system.In addition,the range analysis method is used to determine the weight of the key influencing factors on the particulate combustion rate.This work uses a combination of numerical simulation and experiment to explore in detail the influence of many key influencing parameters on the regeneration performance of the catalytic gasoline engine particulate filter system.The research results will provide important reference value for improving the control effect of gasoline engine exhaust pollutants. |
