Abstract: Biodiesel fuels were used on a direct injection, high pressure common-rail diesel engine. Effects of biodiesel on emissions of exhaust gas and particle number of the diesel engine are studied using an AVL AMA i60 and an Engine Exhaust Particle Sizer (EEPS), respectively. The neat biodiesel, two different blends of petroleum diesel/biodiesel (10% and 20%, v/v biodiesel blends), and the base petroleum diesel (B100, B10, B20 and B0 fuels) were tested without engine modification. For all test fuels, the particle number and size distribution show unimodal or bimodal log-normal distribution. With the biodiesel blend ratios increasing, the number of nucleation mode particles increases and accumulation mode particles decreases, and the total particle number ascend at most engine operating conditions, especially at higher engine load. Nucleation mode particles dominates the total particle number, and accumulation mode particles shows more effects at lower engine load with lower blend ratios of biodiesel fuel.

Key words: diesel engine, fuel, biodiesel, emission, particle number