Reactive molecular dynamics simulations of multicomponent models for RP-3 jet fuel in combustion at supercritical conditions: A comprehensive mechanism study

The aeroengine combustors frequently operate at temperatures and pressures higher than the critical values of the fuels. In this work, the combustion mechanisms and kinetic parameters of two multicomponent models for RP-3 jet fuel are investigated using reactive force field molecular dynamics (ReaxFF-MD). This study reveals that C-C bond dissociation, H-abstraction, and isomerization dominate the initial combustion, with the main products of C1-C3 species, & BULL;OH and & BULL;OOH radicals. The reactions related to the formation and consumption of the radicals play a crucial role in the fuel combustion process. Some radicals rupture into smaller species by releasing C2H4 species. The cracked small molecules are further oxidized and react with radicals to produce large amounts of H2O molecules. The apparent activation energies of the two models are predicted to be 36.40 and 38.04 kcal/mol, judged by the variations in the number of total reactants at different temperatures. The simulation results are in good agreement with the experimental data at high pressures. Finally, the reactants and major product distributions of the two- and three-component fuels under fuel-rich, stoichiometric and fuel-lean combustion are studied. A comprehensive mechanism is developed by simulating the supercritical combustion of two surrogate fuels.