A synthetic skeletal mechanism for combustion simulation of acetone-n-butanol-ethanol mixture and its components in diesel engines

Although acetone, ethanol, n-butanol, and acetone-n-butanol-ethanol (ABE) were successively proved to be alternative resources for IC engines, their combustion characteristics in real engines were rarely compared, which is essential in searching for reliable alternative fuel. Therefore, a comprehensive skeletal mechanism including 110 species and 554 reactions was established herein for predicting the combustion behavior of ABE mixture and individual components in diesel engines. It was generated by the coupling of reduced acetone, n-butanol, ethanol, n-heptane, toluene, and polycyclic aromatic hydrocarbon (A(1)-A(7)) sub-mechanisms, and sensitivity analysis was employed to optimize the coupled mechanism. Important indicators such as ignition delay, laminar flame speed, premixed flame species concentration and engine combustion were used to extensively verify the mechanism. The findings revealed that the experimental combustion characteristics of acetone, n-butanol, ethanol, and ABE mixtures are well reproduced by the mechanism, indicating its suitability in practical engine combustion simulation. And then a drop-in fuel test was carried out by a 3D CFD model coupled with the current mechanism to ascertain the combustion and emissions behaviors of ABE with the different formulation and individual components.

Automated summary

A comprehensive skeletal mechanism was established to predict the combustion behavior of ABE mixture in diesel engines, which was validated through sensitivity analysis and key indicators verification. Finally, a drop-in fuel test was conducted using a 3D CFD model coupled with the current mechanism to study the combustion and emissions behaviors of ABE with different formulations and individual components.