| Summary: | Problems related to security of supply and environmental issues have led the research to find and investigate the possibility for short and long term replacement of conventional petrochemical fuels. In the aviation industry two alternatives have been indicated as possible substitutes to pure kerosene based fuels: blends of kerosene and biodiesel as well as blends of kerosene and Fischer- Tropsch synthetic fuels. Chemical kinetic studies have widely investigated the performance of pure kerosene, pure methyl esters as surrogates of biodiesel, as well as of mixtures of kerosene and biodiesel. A comprehensive theoretical model for the oxidation of blends of kerosene, biofuels and synthetic fuels is proposed in this work, the biofuel portion being represented for the first time by methyl tridecanoate (MTD), a methyl ester with a carbon chain of 13 carbon atoms and chemical formula C14H2802, the synthetic fraction by heptanes. Therefore this work has produced a novel and an original mechanism containing fuels of different characteristics combined in a single scheme and provides a chemical kinetic mechanism for a large methyl ester not previously reported in the current literature. The model development has undergone through the preliminary construction of a reaction mechanism including kerosene and methyl butanoate (MB), the AFRM v2.0 (Aviation Fuel Reaction Mechanism version 2.0). AFRM v2.0 has been updated through a multi-parameter optimization, including the addition of the reactions for the breakdown of the C-14 methyl ester and a set of reactions for the oxidation of heptane. The final scheme consists of surrogate kerosene components n-decane and toluene, a surrogate FAME (methyl tridecanoate), and a surrogate of the synthetic paraffinic portion, heptane. The scheme also includes NOx, SOx and PAH chemistry. Perfectly Stirred Reactor simulations were compared to experimental results from Dagaut et al. for the oxidation of bio-kerosene and pure heptane in a Jet Stirred reactor at different fueV02 equivalence ratios. To investigate the combustion behaviour of the alternative aviation fuels in a flat premixed flame, an experimental study at a variety of stoichiometries of kerosene, kerosenelbiofuel blends, and Fischer- Tropsch derived kerosene substitutes have been performed. A fine wire thermocouple measures the temperature profile of the flame, and product analysis by online gas sampling provides the major species concentrations (02, CO2, CO) along with NOx. These measurements are complemented by the use of a Planar Laser Induced Fluorescence (PLIF) to provide relative concentration profiles of NO and the reactive intermediate OH.
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