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. •Burning characteristics of acetone–butanol–ethanol (ABE) and diesel blend droplets.•The addition of ABE in diesel reduces soot generation propensity.•ABE-diesel blends have longer ignition delay and faster burning rates than diesel.•Micro-explosion occurs at the end of flame for all testing ABE-diesel blends.•Micro-explosion performance varies non-linearly with ABE content.