Generation of Model Diesel Particles by Spark Discharge and Hydrocarbon Condensation

This study was conducted in order to generate model particles which were similar to particles in diesel emission. Spark discharge was used for carbon agglomerates and hydrocarbon condensation for particles that consist of carbon agglomerates and hydrocarbon. The size of the carbon agglomerates, whose mean size were 30 and 70 nm, ranged between 15 and 200 nm, and the total number concentration of the particles ranged from 3 to $5{\times}10^7#/cm^3$ as the controllable variables in spark discharge generator changed. The result of the hydrocarbon condensation experiment showed that the final sizes of the particles enlarged by condensation did not depend on the initial sizes, but the maximum condensational growth of carbon agglomerates by dodecane ($C_{12}H_{26}$) condensation was 112 times the initial size of 40 nm, while the size of the agglomerates by benzene ($C_6H_6$) was 3.25 times its initial size.