Simulation Analysis And Experimental Verification GPF Technology Of GDI Engines

With the improvement of power performance and fuel economy of GDI engine,the level of particulate matter in the GDI engine emissions increases.In order to meet the requirements about the PN and PM limit number in GDI engine emissions of the upcoming European ? ? the five and six criteria,the GPF closed purification technology is put forward.Using the GPF closed purification technology can reduce the GDI engine PM value,but the study of this technology in our country is not yet mature.Therefore,through the test of one domestic 2.0 TGDI engine,the characteristics of the particulate matter in the emissions are analyzed in this article.The finite element numerical model of GPF is established by FIRE software,the effects of different inlet flow,hole mesh number and carrier length on the pressure drop characteristic,filtration efficiency,temperature field and flow field are studied,the GPF entity is optimized in result,and its feasibility is analyzed by the test method.The research content has an important significance on the application promotion of GPF closed purification technology.GPF import flow increase lead to the pressure drop of value increase as well.Hole mesh increase pressure drop value increases at the same time,the temperature field,the temperature fell slightly,velocity is lower,but it has improved the filtration efficiency,especially for small diameter of particle filtering.GPF as carrier length increases,the pressure drop values increased slightly,but the filtration efficiency are increased,the temperature field changed little,just slow temperature rise to stable value,flow velocity slightly low,favorable to the accumulation of particulate matter.Comprehensive consideration,GPF enlarged hole mesh and carrier length increased while causes the pressure drop is worth,but the filtration efficiency will be improved,temperature and flow rate changed little.Therefore the GPF optimized can increase hole mesh and carrier of appropriate length.After the selection of GPF type,the maximum pressure drop measured in the experiment is 26.1 KPa,the impact on engine torque loss is little,and it can meet the meet requirements of power performance and fuel economy of GDI engine,the filtration efficiency is all above80%,the filtering effect is good.By the analysis of trapping effect of particles number,theresult shows that it has an good effect on the filter of different diameters particles,the particulate trap effect on small particle size produced by GDI engine of is especially obvious,the feasibility of closed purification technology is confirmed.