Expansion heat release and thermal efficiency of acetone-butanol-ethanol-diesel blended fuel (ABE20) combustion in piston engine

Abstract

The intermediate product of the butanol production process, acetone-butanol-ethanol (ABE) mixture, is a promising alternative fuel for diesel engine as its physical properties are resemble to diesel fuel. This study explores heat release pattern and thermal efficiency as a consequence of combustion of the 20% v/v ABE blended with diesel (ABE20) in a stock single-cylinder diesel engine. All parameters were studied in steady-state condition of medium and full loads at a constant engine speed of 1400 rpm. ABE20 presents a slightly lower thermal efficiency with comparable energy consumption compared to diesel fuel. A longer ignition delay was observed for ABE20 and the diffusion combustion regime was shortened in duration. The cylinder pressure-derived heat release in the expansion stroke discloses a different specific heat ratio during ABE20 combustion.