A PHYSICALLY-BASED, CONTROL-ORIENTED DIESEL PARTICULATE FILTER (DPF) MODEL FOR THE APPLICATIONS OF NO/NO_2 RATIO ESTIMATION USING A NO_X SENSOR

摘要

This paper presents a physically-based, control-oriented Diesel particulate filter (DPF) model for the purposes of NO and NO_2 concentration estimations in Diesel engine aftertreatment systems. The presence of NO_2 in exhaust gas plays an important role in selective catalytic reduction (SCR) NO_x reduction efficiency. However, current NO_x sensor cannot differentiate NO and NO_2 from the total NO_x concentration. A model which can be used to estimate NO and NO_2 concentrations in exhaust gas flowing into the SCR catalyst is thus necessary. Current aftertreatment systems for light-, medium-, and heavy-duty Diesel engines generally include Diesel oxidation catalyst (DOC), DPF, and SCR. The DPF related NO/NO_2 dynamics was investigated in this study, and a control-oriented model was developed and validated with experimental data.