An experimental study of the burning characteristics of acetone–butanol–ethanol and diesel blend droplets

Acetone–Butanol–Ethanol (ABE), the intermediate product to produce bio-butanol is used as an alternative fuel directly to eliminate needless production costs. In this study, the droplet burning characteristics of neat ABE, diesel and ABE-diesel blends (10%, 20%, 30%, 50% of ABE (vol%)) fuels are investigated by the droplet free falling technique under atmospheric pressure. The initial droplet temperature and diameter are about 300 K and 235 μm respectively. The ambient temperature around the flat-flame burner is about 1123 K, and the residual oxygen concentration is 21 vol%. The results show that the addition of ABE not only increases the average burning rate and the ignition delay of droplets, but also reduces soot emissions. Meanwhile, ABE-diesel blends droplets occur micro-explosion at the end of flame because of the large difference in volatility between ABE components and diesel, which distinctly shortens the burning duration of ABE-diesel blends. In addition, with the increase of ABE content, the micro-explosion performance and overall burning rates increase first and then decrease, which indicates the existence of an optimal volume blend ratio around 30% ABE content for ABE-diesel blends that makes explosion performance and overall burning rates reach the top.