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This work presents and validates a new methodology that determines the adiabatic ignition delay of a hydrocarbon-based fuel using several nonadiabatic ignition delay measurements. The new methodology was developed and validated in a numerical modeling and then applied to propane autoignition experiments to determine the adiabatic ignition delay of the fuel, the so-called measured adiabatic ignition delay. Propane ignition delays were measured in a wide range of low to intermediate gas temperatures ranging from 769 to 952 K, at pressures of 23–30 bar, and at equivalence ratios of approximately 0.5 and 1.0 for a rapid compression machine (RCM). Application of the new methodology removed the effect of heat transfer on measured ignition delay, thus reporting the adiabatic ignition delay free from facility heat-transfer effects. The measured adiabatic ignition delays from the RCM are close to the ones measured by a shock tube.

The autoignition process of different propane mixtures was studied to determine how the diluent choice (helium and argon/nitrogen) affects the ignition delay, the production of excited radicals, and the overall combustion process. An optically accessible rapid compression machine, high-speed camera, flame spectrometer, and numerical model were used to investigate the combustion process. The ignition delay times were measured at a wide range of compressed gas temperatures from 860 to 950 K, a compressed gas pressure of approximately 34 bar, and two equivalence ratios of 1.0 and 1.5. Chemiluminescence at wavelengths of 309, 555, 590, and 623 nm from the decay of excited radicals was detected during the autoignition process, and their respective intensities were measured and compared at various test conditions. A new kinetic model was built by combining reaction rates of excited radicals and species from the literature. The new model was validated against the measured ignition delay data of this work. The ignition delay and some of the excited radicals show a strong dependency on the diluent choice. A new numerical model was used to include the effect of heat transfer and the diluent choice in the temperature calculation and ignition delay modeling and measurements. Using the new numerical model, we found that the measured ignition delays are not dependent on the diluent choice.

There has been considerable progress in the area of fuel surrogate development to emulate gasoline fuels’ oxidation properties. The current paper aims to review the relevant hydrocarbon group components used for the formulation of gasoline surrogates, review specific gasoline surrogates reported in the literature, outlining their utility and deficiencies, and identify the future research needs in the area of gasoline surrogates and kinetics model.