Influence of fuel quality on mixture preparation and exhaust emissions from diesel engines with common rail system

The objective of mixture preparation process in Diesel engines is obtaining full combustion and minimum harmful compounds of exhaust emissions. The injection process is the most important from the viewpoint of mixture preparation process. The experimental data of fuel spray atomization and droplet velocities of three different fuels with varied viscosity are presented in the paper. The research was performed using the PIV and LDYand PDPA laser equipment. The tested fuels were Diesel oils with varied viscosity and RME. The injection pressure varied from 50 MPa to 130 MPa. The fuels were injected to test chamber with optic access in atmospherical pressure and temperature. Pressure increase caused a continuous reduction in fuel drop diameter. The fuels with higher viscosity generated bigger droplets than the fuel with lower viscosity.