Experimental and Kinetic Modeling Study of the Pyrolysis and Oxidation of Decalin

Decalin is a model compound for bicyclic naphthenes found in jet fuels and coal-, oil-shale-, tar-sand-derived fuels, and it is also a potential endothermic fuel for hypersonic flight. Additionally, decalin is a reference component in surrogate mixtures of jet fuels. New shock tube ignition delay time measurements have been performed for decalin/air mixtures at elevated-pressure conditions relevant to practical combustion engines for varying pressure (9−15 and 35−48 atm), equivalence ratio (Φ = 0.5 and 1.0), and temperature (990−1300 K). An automatic kinetic generator, the MAMA code, has been applied to develop a semi-detailed submechanism for decalin decomposition at high-temperature conditions. Kinetic simulations are compared to the measured ignition times with adequate agreement. Sensitivity analysis indicates limited importance of decalin unimolecular decomposition and hydrogen abstraction from decalin and moderate importance of the decomposition of C10H17 radicals in predicting ignition times. The new decalin submechanism further advances the kinetic understanding of pyrolysis and oxidation of heavy hydrocarbons found in practical fuels.