Experimental Investigation on Particle Number and Size Distribution of a Common Rail Diesel Engine Fueling with Alternative Blended Diesel Fuels

An EURO 3 certified common rail diesel engine was fueled with pure petroleum diesel (EURO 4 standard) and three different alternative blended diesel fuels, 10% biodiesel blended diesel (B10), 10% gas to liquid blended diesel (G10) and 10% water emulsified diesel (E10). Tests were performed at different engine speeds and load states. Particle number concentration and size distribution data were obtained from an engine exhaust particle sizer (EEPS). Over all the working conditions, total particle and nucleation mode particle number concentration among these fuels from high to low were in this order: B10, E10, pure diesel and G10. Proportions for nucleation mode particle over all the operating states in that order were 89%, 82%, 59% and 66%. Particle size distributions of B10 and E10 presented bimodal logarithmic distributions with outstanding nucleation mode peaks at all working conditions. G10 and pure diesel presented unimodal logarithmic distributions at full load conditions, and presented bimodal logarithmic distributions with nucleation mode peaks at part load conditions. Accumulation mode particle number concentration had a common trend with smoke intensity, but nucleation mode particle data had no clear relationship to smoke intensity. The results indicate that G10 has less particle emissions than pure diesel, the increases in both total particle and nucleation mode particle emissions caused by B10 and E10 need to pay a great concern.