Compared to gaseous fuels, notably fewer fundamental flame data exist for practical jet fuels. Such fuels require precision and rather complex control in order to be introduced into the gas phase without changing the fuels' composition. Additionally, the modeling of their kinetics is a daunting task given the wide range of heavy and complex hydrocarbons that they contain. On the other hand, the under standing of the burning characteristics of jet fuels is of significant importance for air-breathing propulsion. The development of reliable surrogate fuels that mimic the behavior of the real fuels is a promising approach towards the development of kinetics mechanisms that can be eventually used in LES simulations of combustors. In the present study, extinction strain rates and ignition temperatures of a wide range of jet fuels were experimentally determined in the counter flow configuration under non-premixed conditions. Similar measurements were also made for single-component hydrocarbon fuels and surrogate fuels and were compared with those obtained for the jet fuels. The experiments were conducted at atmospheric pressure and elevated temperatures. For single-component hydrocarbon fuels, fuels with lower carbon number were found to be more resistant to extinction and have greater ignition propensity. The results for the jet fuels revealed that there is a large variation in both extinction and ignition limits. Jet fuels with similar extinction behavior were found to exhibit a rather different ignition response. Two recently proposed JP-8 surrogates were also tested, and both the ignition and extinction states of a reference JP-8 fuel were not predicted satisfactorily. Both surrogates were found to exhibit a more robust combustion behavior compared to JP-8, as manifested by their increased ignition propensity and their increased resistance to extinction.
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