Study on characteristics of particulate emission of diesel aftertreatment with reciprocating flow

In this article, in order to optimize diesel aftertreatment system with periodically reciprocating flow (PRF), an experimental study is conducted to investigate its characteristics such as pollution emissions, regeneration of diesel particulate filter (DPF), concentration, and size distribution of particulate matter (PM) escaped as well as temperature distribution under unidirectional flow and PRF operating conditions. The effects of reciprocating flow cycle and exhaust gas flow on the performance of aftertreatment system are investigated in detail. The energy efficiency analysis of the aftertreatment system is also carried out. Experimental results show that (a) as the temperature is lower than the light-off threshold of combustible gas, the aftertreatment system cannot restrain the formation of second particles under the low-temperature condition of unidirectional flow; and (b) the aftertreatment system demonstrates excellent performance of trapping particles and filter regeneration as the symmetrical temperature distribution is formed. The PM filter efficiency alpha PM is 92%, and the specific energy consumption beta is 124% for symmetrical temperature distribution; (c) the increase in reciprocating flow cycle could lead to the shifting of the temperature profiles, and this would affect the particle size distribution; (d) a certain increase in exhaust gas flow from engine would have insignificant change for the temperature distribution; and (e) the critical energy efficiency eta c of the system could reach 96.61%.

Automated summary

This article conducts an experimental study on the characteristics and performance of a diesel aftertreatment system with periodically reciprocating flow, finding that the system performs well in trapping particles and filter regeneration under symmetrical temperature distribution. The critical energy efficiency of the system can reach 96.61%.