A skeletal chemical reaction mechanism for gasoline-ABE blends combustion in internal combustion engine

Acetone-butanol-ethanol (ABE), serving as the intermediate product in the biobutanol production process, has garnered significant attention as a promising alternative fuel, thanks to its ability to avoid the costs and energy consumption associated with biobutanol purification, as well as its potential to improve thermal efficiency and reduce pollutant emissions of internal combustion engine. However, to date, there has been limited in-depth research into the chemical reaction mechanism for the combustion of gasoline-ABE blends and its application in engine simulations. In this study, a skeletal chemical reaction mechanism of gasoline-ABE blends was constructed, which consists of 87 components and 387 reactions, using a manifold trajectory-based dimension reduction algorithm developed by our research group. The findings illustrate that the skeletal mechanism can accurately predict ignition delay, laminar flame speed, and premixed flame species profiles for each component within gasoline-ABE blends, including isooctane, n-heptane, toluene, acetone, butanol, and ethanol. The skeletal mechanism was subsequently coupled with a CFD model to further validate its efficacy in engine combustion simulation. The results indicate that the combustion characteristics of gasoline-ABE blends in the engine can be reliably reproduced. After conducting a comprehensive simulation analysis, it is revealed that gasoline blended with 30 vol% ABE361(A:B:E = 3:6:1) exhibits a shorter initial combustion duration, an extended main combustion duration, reduced CO emissions, but also increased NOx emissions.