Laminar burning velocity and explosion characteristics of a lignocellulose-derived bio-jet fuel at elevated pressures and temperatures

Abstract

The production of aviation fuel from lignocellulose is inexpensive and has high selectivity and atom economy. The authors reproduced a mixed fuel of a bio-jet fuel candidate, which was obtained from lignocellulose using the hydropyrolysis vapor upgrading process. The combustion characteristics of this fuel have not been studied yet, so the laminar burning velocity and explosion characteristics of the fuel were investigated under a wide range of conditions in a constant volume combustion chamber at initial pressures of 1, 2, and 4 bar, initial temperatures of 400, 435, and 470 K, and equivalence ratios of 0.7–1.4. The results show that the laminar burning velocity of the fuel is maximum at the equivalence ratio of 1.1–1.2, which is close to that of RP-3 and Jet A-1 but smaller than that of bio-jet fuels produced through hydroprocessed esters and fatty acids. The simulation shows good agreement with experiment at elevated temperatures. The explosion intensity increases with an increase in the equivalence ratio under elevated initial pressures due to pressure oscillation. The dominant frequency of the pressure oscillation is slightly higher than that of the brightness oscillation, both of which are between 2500 and 3000 Hz The reduction of Markstein length is correlated with pressure oscillations and brightness oscillations.