A comparative study of combustion chemistry of conventional and alternative jet fuels with hybrid chemistry approach

Alternative jet fuels are expected to enter into the market in the next decade. Their use in commercial aviation is hindered by the lack of inexpensive fuel certification methods. Approaches that can quickly and accurately unravel the combustion chemistry of alternative fuels are essential to enable fuel certification and thus alternative jet fuel utilization. HyChem (hybrid chemistry), an unconventional approach to describing the combustion chemistry of multicomponent jet fuels, decouples the fuel pyrolysis and the oxidation of the decomposed products both temporally and spatially. The present work applies the HyChem models to compare one conventional, petroleum-derived jet fuel (designated as A2 fuel), with an alternative, bio-derived jet fuel (designated as C1 fuel). Computational results indicate that C1 decomposes to primarily iso-butene in a faster rate, while A2 decomposes to mostly ethylene. The ignition delay time of the two fuels are also compared over different temperature regions. It is found that C1 ignites slower than A2 at temperatures higher than 1300 K, but faster than A2 in the temperature region of 1000-1200 K.