Oxidation kinetic mechanism of n-decane under high temperature and pressure: a first-principles molecular dynamics study

The n-decane/air (C₁₀H₂₂/air) combustion reaction kinetics has attracted much research attention because of its potential application in the aerospace field. In this work, C₁₀H₂₂ oxidation in O₂ under high temperature and pressure is simulated based on the first-principles molecular dynamics method for the first time. Our results show that C-C bond breaking and H-abstraction are the two main initial reactions in the oxidation process of C₁₀H₂₂. However, there exists an obvious difference under high and atmospheric pressures. Under high pressure, C-C bond dissociation reactions of hydrocarbon molecules are the main reaction types, while H-abstraction reactions are the main reaction types under atmospheric pressure. The radicals (HO₂, OH, O, etc.) play key roles in promoting the oxidation of hydrocarbon molecules. A detailed chemical kinetic model (76 species and 435 elementary reactions), the FP-C₁₀H₂₂ model, of C₁₀H₂₂/air mixture combustion is constructed and verified. The predicted values of FP-C₁₀H₂₂ model on the ignition delay time, laminar flame speed and species concentration of jet stirred reactor (JSR) species concentration are in good agreement with the experimental data.