Ash Accumulation and Transport in Diesel Particulate Filters (Second Report)

- Impact of Active Regeneration Frequency on Ash Distribution -

Abstract

Accelerated ash accumulation techniques were established by means of diesel particulate generator (DPG) in which engine oil injector is installed. Three diesel particulate filter (DPF) samples with different active regeneration frequency were made by DPG then the ash accumulation distribution was observed nondestructively by X-ray computed tomography (CT). As a result, it was clarified that ash distribution is drastically changed by active regeneration frequency, and soot load is important factor on ash transport during DPF regeneration. Scanning electron microscope (SEM) observations of ash both before and after regeneration were also conducted and it was confirmed that ash particle size grows due to crystallization by ash sintering after regeneration. In addition, from the analysis of change in ash accumulation amount before and after regeneration, it was suggested that ash passing through the DPF may occur during active regeneration.