Mechanism of fuel spray preparation and the investigation of fuel sprayed with the Common Rail method using PIV, LDV and PDPA laser methods are presented in the paper. Two fuels with different viscosities were tested. Tests were performed for different fuel injection pressures. The tests indicated significant influence of fuel viscosity on fuel preparation process for Diesel engine, especially on mixture homogeneity which is very important for exhaust emission.
Results of investigations of selected properties of diesel oil on exhaust emissions of diesel engine ave presented. Quantity of individual groups of hydrocarbons in fuel influences the change in the content of main components of exhaust gases. These changes are dependent on thermodynamical parameters prevailing in the chamber (pressure, temperature, swirl). On the basis of engine investigations there was evaluated the influence of aromatic hydrocarbon content on the level of total hydrocarbons, carbon monoxide, nitrogen oxides, and particulates in exhaust gases and smoke were evaluated. Investigations in the experimental chamber confirmed a strong influence of fuel viscosity on the range of fuel stream and its structure.