Evaluation of the combustion characteristics of isolated droplets of Jet A blended with ethanol and butanol

Abstract

[EN] In light of the potential of ethanol and butanol as alternative fuels for blending with conventional kerosene in gas turbine engines, experimental data regarding the burning characteristics of these blends are required in order to better understand their combustion process. In this study, free-falling droplets of Jet A, ethanol, butanol and their mixtures (20% alcohol in Jet A by volume) were examined in a combustion chamber which provides representative conditions of real flames, both in terms of temperature and oxygen availability. Results show that the evolution of droplet diameter for Jet A and its blends with both alcohols are very similar, regardless of the obvious compositional differences. On the other hand, sooting behaviors are found to be quite different, with a clear reduction in the sooting propensity of the Jet A/alcohol mixtures when compared to neat kerosene. These results are consistent with previous studies in gas turbines, suggesting that such blends are viable alternative fuels with similar combustion characteristics to Jet A, but with much less propensity to produce soot. Moreover, this study provides new results on the combustion properties of Jet A/ethanol and Jet A/butanol mixtures, for which very scarce data exist in the open literature.