Experimental investigation on the macroscopic and microscopic spray characteristics of dieseline fuel

The application of dieseline fuel (blends of diesel and gasoline) into compression ignition engines has been intensively investigated in recent years due to its good combustion performance and low smoke emissions. In this study, the main objective was to investigate the spray characteristics of dieseline fuel. Macroscopic spray characteristics in terms of spray morphology and penetration were investigated in a constant volume vessel under elevated ambient pressures using high-speed imaging system, while the microscopic spray characteristics including droplet size and velocity distribution were measured at atmospheric condition using Phase Doppler Particle Analyzer (PDPA) system. The results have shown that the gasoline/diesel blending ratio played an important role in affecting the spray atomization process. With the increase of the gasoline/diesel blending ratio, spray penetration length, droplet mean velocity, and droplet Sauter Mean Diameter (SMD) decreased gradually, especially at low injection pressure and low ambient pressure conditions. Both the results of macroscopic and microscopic studies indicate a better atomization quality can be achieved by increasing the proportion of gasoline in the dieseline.