SOOT PARTICLE SIZE DISTRIBUTION NEAR THE CYLINDER WALL IN A DIRECT INJECTION DIESEL ENGINE

Abstract

Investigation of soot particle size and its distribution inside a direct injection diesel engine provides the idea of how soot particles are distributed in an engine cylinder, particularly near the cylinder wall. The objective of the present study is to obtain soot particles size distribution near the cylinder wall which contributes to the issue of soot in lubricating oil. The study was performed numerically by post-processing CFD simulation data with in-house Matlab routines. Hiroyasu soot formation, Nagle & Strickland-Constable oxidation and Wersborg soot coagulation models were adapted to calculate the soot particle size in this study. Soot particle size calculation, which was carried out post-processed, reduced the simulation time and computational effort. Results obtained showed that soot particles with a size smaller than 50 nm were found in the squish region particularly near the cylinder wall. As much as five percent of the total number of soot particles tracked were found in the boundary layer at the cylinder wall.

Keywords

• CFD
• Coagulation
• Particle tracking
• Soot size distribution
• Squish region