Abstract
PM emission originated in combustion process of diesel engine should be reduced to keep the clean air environment. However, the detail characteristics about the primary and aggregate diameter of the PM were still unknown and they are needed for more physically accurate measurement and more effective improvement of exhaust PM emission. In this study, the size distributions of Dry-Soot in PM emission were reported. PMs in the tail-pipe emission were sampled from three type diesel engines. Sampled PM was chemically treated to separate the solid carbon fraction from other fractions such as SOF. The electron microscopic and optical-manual size measurement procedure was used to determine the primary size distribution. The centrifugal sedimentation method was applied to measure the Stokes equivalent diameter of the aggregate size of carbon PM cluster. They were discussed with aero-dynamic PM diameter measured by SMPS. Also, the effects of fuel properties and engine types on primary and aggregate PM diameters were discussed.
