Formulation of a Reduced Chemical Kinetic Mechanism for the Combustion Modelling of Iso-Pentanol Fuel

In this paper, the formulation of a reduced chemical kinetic mechanism for iso-pentanol fuel is presented. First, the main reaction pathway and pertinent key species for iso-pentanol oxidation were identified. Then, the detailed chemical kinetic mechanism for iso-pentanol was reduced using reduction techniques which included directed relation graph, isomer lumping and temperature sensitivity analysis, where a reduced mechanism of 92 species and 444 reactions was obtained. The reduced mechanism for iso-pentanol was validated against experimental data as well as detailed mechanism predictions under zero-dimensional shock tube auto-ignition and jet-stirred reactor (JSR) conditions, at initial temperatures from 650 K to 1350 K, initial pressures from 10.1 bar to 60 bar and equivalence ratios between 0.5 and 2. Under the shock tube auto-ignition conditions, more than 85% of the experimental measurements and detailed mechanism predictions for the ignition delay (ID) of iso-pentanol were replicated by the reduced mechanism. Similarly, species profiles under the JSR conditions which were related to the formation of oxidation, aldehyde and emissions for iso-pentanol were also reproduced. Furthermore, the rate of production analysis revealed that the elementary reactions associated to the oxidation of iso-pentanol in the detailed mechanism were successfully retained in the reduced mechanism. Meanwhile, the computational runtime was saved by three times when the reduced mechanism was implemented to model the simulations. These results therefore indicate that the reduced mechanism developed for iso-pentanol is sufficient and reasonable.