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Thermal cracking of n-decane and n-decane in the presence of several fuel additives are studiedinorder to improve the rate of thermal cracking by using reactive moleculardynamics (MD) simulations employing the ReaxFF reactive force field.From MD simulations, we find the initiation mechanisms of pyrolysisof n-decane are mainly through two pathways: (1)the cleavage of a C–C bond to form smaller hydrocarbon radicals,and (2) the dehydrogenation reaction to form an H radical and thecorresponding decyl radical. Another pathway is the H-abstractionreactions by small radicals including H, CH3, and C2H5. The basic reaction mechanisms are in good agreementwith existing chemical kinetic models of thermal decomposition of n-decane. Quantum mechanical calculations of reaction enthalpiesdemonstrate that the H-abstraction channel is easier compared withthe direct C–C or C–H bond-breaking in n-decane. The thermal cracking of n-decane with severaladditives is further investigated. ReaxFF MD simulations lead to reasonableArrhenius parameters compared with experimental results based on first-orderkinetic analysis. The different chemical structures of the fuel additivesgreatly affect the apparent activation energy and pre-exponentialfactors. The presence of diethyl ether (DEE), methyl tert-butyl ether (MTBE), 1-nitropropane (NP), 3,6,9-triethyl-3,6,9-trimethyl-1,2,4,5,7,8-hexaoxonane(TEMPO), triethylamine (TEA), and diacetonediperodixe (DADP) exhibitremarkable promoting effect on the thermal cracking rates, comparedwith that of pure n-decane, in the following order:NP > TEMPO > DADP > DEE (∼MTBE) > TEA, which coincideswithexperimental results. These results demonstrate that reactive MD simulationscan be used to screen for fuel additives and provide useful informationfor more comprehensive chemical kinetic model studies at the molecularlevel. [ABSTRACT FROM AUTHOR]