The Process of Diesel Particulate Filter Regeneration under Real Driving Conditions

Abstract

The global automotive industry is actually facing complex challenges to ensure solutions that reduce transportation related environmental impact. Because of this, solution were created to reduce exhaust gas emission, like for example DPF [1]. This study was conducted to examine the process of Diesel particulate filter automatic active regeneration during on-road mileage accumulation of Diesel passenger cars. The Diesel test vehicles used in this study were equipped with Diesel oxidation catalysts (DOC), lean NOx trap (LNT, only one vehicle type) and two types of Diesel particulate filter: DPF and FAP (French: filtre à particules) as aftertreatment systems, and satisfied either the Euro 5 or the Euro 6 emissions standards, depending on the vehicle. The test vehicles’ mileage before testing was at least 30 000 km. The soot accumulated during normal use of the vehicles on various types of routes. Collected and processed data were obtained over a distance of 15 000 km. During soot accumulation and DPF regeneration, many parameters from the electronic control unit (ECU) were recorded, i.e. vehicle velocity, engine speed, accumulated soot mass, differential pressure and temperatures at the inlet and outlet of the DPF. The distance covered during the soot accumulation phase depended on the driving conditions, and was sometimes as high as 850 km. During the regeneration process, the temperature at the DPF inlet sometimes rose above 500 °C, and above 600 °C at the outlet, and the differential pressure sometimes reached over 250 mbar.