摘要

In this study, the injection characteristics of diesel and blends of diesel and gasoline were investigated on a common rail injection system, using two nozzles with different orifice diameter and opening pressure. The volumetric injection rate curves, volumetric and mass cycle injection quantities and the coefficient of variances within a range of changed injection pressure and energizing time were investigated. It was found that increased gasoline proportion in fuel blends produced higher peak volumetric injection rates and volumetric cycle injection quantities than those of diesel, but comparative mass cycle injection quantities with diesel. The nozzle opening pressure and the orifice diameter also influenced the injection rate curve and cycle injection quantity, but the influential behavior depended on the energizing time and injection pressure, which might be attributed to different needle lifting motions. Higher peak injection rate and cycle injection quantity were found with increased orifice diameter, injection pressure and energizing duration. Cycle injection quantity variance was strongly related with the length of energizing time and injection pressure, but nozzle parameters and test fuels were not observed to significantly influence the injection quantity variance.