Experimental studies on the particulate matter emission characteristics of a lateral swirl combustion system for direct injection diesel engines

Abstract

To analyze the particulate emission characteristics of a lateral swirl combustion system (LSCS), experimental research on a single-cylinder diesel engine was done and compared against the Turbocharger-Charge Air Cooling-Diesel Particle Filter Series combustion system (TCDCS) at different conditions. Compared to the TCDCS, the LSCS presents better combustion performance and lower total particle emission characteristics: As for the LSCS, the vast majority of the particle number size distributions shifted downward, indicating a decrease in the particle number concentration. The total particle number and mass concentrations of the LSCS decreased by 8.7–62.4% and 15.2–55.6% at various loads. The number concentration of particles smaller than approximately 8 nm increased for the LSCS, which can be attributed to the higher temperature and more thorough fuel/air mixture, facilitating the oxidation of large particles into small particles. Combined with the simulation, the LSCS perfectly exerts the wall-flow-guided effect, remarkably improving the fuel/air mixing quality and reducing the local over-concentration regions, which can inhibit the formation of particles. Hence, the LSCS effectively reduces the particle number and mass concentrations, exhibiting excellent particulate emission characteristics.