Construction of a Skeletal Oxidation Mechanism for 2,5-Dimethylfuran Using Decoupling Methodology and Reaction Class-Based Global Sensitivity Analysis

As
a promising alternative biofuel, 2,5-dimethylfuran (DMF) has
caused great concern recently. In this research, a new skeletal oxidation
mechanism for DMF is built by merging the decoupling methodology with
the reaction class-based global sensitivity analysis. First, the global
sensitivity and path sensitivity analyses are used to identify the
dominant reaction classes in the fuel-related submechanism of DMF.
Then, the important isomers in the dominant reaction classes are chosen
with the rate of production analysis. In addition, the vertical reaction
lumping is performed to obtain global reactions for the reaction classes
based on the steady-state assumption of the involved intermediate
radicals. A skeletal C4–C6 submechanism
is obtained. Based on the decoupling methodology, an original skeletal
mechanism of DMF is constructed by adding the skeletal fuel-related
sub-mechanism into a compact C0–C3 submechanism.
Third, the reaction rate coefficients involving the fuel-related species
are tuned within their uncertainty ranges through the genetic algorithm
to ameliorate the predictions of the skeletal mechanism on autoignition
times in shock tubes and key species evolution in jet-stirred reactors
(JSRs). The final skeletal mechanism for DMF is obtained, consisting
of 57 species and 212 reactions. The satisfactory agreement between
the measurement and prediction shows that the final skeletal mechanism
is able to well capture the ignition and combustion phenomenon of
DMF under wide operating conditions.