Modeling of Diesel Particulate Filter Regeneration under the Urban Dynamometer Driving Schedule

Particulate Matter (PM) emissions from either on-road or off-road diesel engines are subject to federal and/or state standards. Recently, Diesel Particulate Filters (DPF) have been shown to be the most efficient way to reduce the PM emissions. However, DPFs need to be regenerated periodically. In order to predict when to regenerate the DPF under real-time driving conditions, a regeneration model for the DPF is needed. In this study, a transient one-dimensional model is used to track gas and solid temperatures and the particulate deposit thickness, and is studied under the Urban Dynamometer Driving Schedule (UDDS) which has variable exhaust flow rate, exhaust temperature, and PM concentration. In order to determine the best conditions, the thermal regeneration is initiated at different time points during the UDDS cycle. Moreover, we also calculate the transient temperature profile and the deposit thickness for each case. We found that the regeneration efficiency is the highest when the regeneration is initiated at 180 seconds into the UDDS cycle which corresponds to a period of extended city driving without stopping.