Experimental Study on Gas Flow Uniformity in a Diesel Particulate Filter Carrier

A Diesel Particulate Filter (DPF) is a critical device for diesel engine exhaust products treatment. When using active-regeneration purification methods, on the one hand, a spatially irregular gas flow can produce relatively high local temperatures, potentially resulting in damage to the carrier; On the other hand, the internal temperature field can also undergo significant changes contributing to increase this risk. This study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle (DTI) condition by means of bench tests. It is shown that the considered silicon carbide carrier exhibits good flow uniformity, with a temperature deviation of no more than 2% with respect to the same radius measurement point at the outlet during the regeneration stage. In the DTI test, the temperature is relatively high within r/2 near the outlet end, where the maximum temperature peak occurs, and the maximum radial temperature gradient is located between r/2 and the edge. Both these quantities grow as the soot load increases, thereby making the risk of carrier burnout greater. Finally, it is shown that the soot load limit of the silicon carbide DPF can be extended to 11 g/L, which reduces the frequency of active regeneration by approximately 40% compared to a cordierite DPF.