Combustion Behavior of Jet A Droplets and its Blends With Butanol
In light of the potential of butanol as an alternative fuel for blending with petroleum fuels such as gasoline, diesel or Jet A, experimental data regarding the burning characteristics of these blends are required in order to better understand their combustion process. In this study, freely-falling droplets of butanol, Jet A, and their mixtures (10, 20 and 50% butanol by volume) were examined in a combustion chamber which provides representative conditions of real flames, both in terms of temperature and oxygen availability. The combustion characteristics reported here include evolution of droplet sizes, burning rates, soot measurements, and the occurrence of microexplosions and soot shells. Results show that the evolution of droplet diameter for butanol, Jet A and their blends are very similar, regardless of the obvious compositional differences. Sooting behaviors are found to be quite different, with a clear reduction in the sooting propensity as the butanol content in the fuel increases. These results are consistent with a previous study in a gas turbine showing similar performance among Jet A and its blends with butanol, suggesting that such mixtures are promising alternative fuels with very similar combustion characteristics to Jet A, but with much less propensity to soot. Moreover, this study provides new results on the combustion properties of Jet A/butanol blends, for which very scarce data exist in the open literature.