Impact of thermophoresis factor on soot particle trajectories near the in-cylinder wall in a diesel engine

It is essential to study the behaviour of soot particles in the engine cylinder, including movement and physical properties during engine operation, for further analysis of performance characteristics and engine emissions. This research aims to determine the size distribution of soot particles near the cylinder wall, leading to soot in lubricating oil. The research was carried out numerically using in-house MATLAB routines to post-process CFD simulation results. In this analysis, the soot particle size was calculated using the Hiroyasu soot formation, Nagle & Strickland-Constable oxidation, and Wersborg soot coagulation models. In addition, the simulation time and computing effort were minimized by using a post-processed soot particle size estimate. According to the findings, soot particles smaller than 50 nm were found in the squish area, especially near the cylinder wall. The average value of the final location of the particles tracked from all zones in the trajectory analysis varies between 0.4 and 3.1% of the magnitude closer to the cylinder wall relative to the particles tracked without the thermophoresis factor.

Automated summary

This study numerically analyzed the behavior and distribution of soot particles generated during combustion in the engine cylinder, revealing that soot particles smaller than 50 nm are mainly located in the squish area, which has a significant impact on engine performance and emissions.