Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 03, 2017 - September 06, 2017
To maintain the performance of after-treatment devices, current diesel engine regulations require the use of on-board diagnostics (OBD). For diesel particulate filters (DPF), the pressure drop across the DPF is monitored to determine problems in the performance or PM over-accumulation. It is known that heavy accelerations during cold starting cause a sudden decrease in DPF pressure-drop. This appears to be caused by water condensed in the exhaust pipe, but no detailed mechanism has been established. The present study developed an experimental apparatus that reproduces heavy accelerations with high gas flow rate and a water supply. The results indicated that the sudden decrease in the DPF pressure drop is caused by a peeling-off and separation of the soot cake from the walls of the DPF, and the increase of the water flow rate causes the decrease of the DPF pressure drop.
