Combustion chemical reaction mechanism and kinetic analysis of RP-3 aviation kerosene/low carbon alcohol blends

Abstract

Adding small molecules of low-carbon alcohol fuel to aviation kerosene can improve the reaction activity and shorten the ignition delay time. Low-carbon alcohols accumulate important intermediates at low temperatures and undergo rapid cracking and oxidation at high temperatures to produce reactive radicals such as OH, H2O2, C2H4, and CH3. These reactive radicals play a key role in accelerating chain reactions and reducing emissions of pollutants such as CO, HC, and PM. In order to accurately predict the combustion characteristics of large-molecule hydrocarbons and small-molecule low-carbon alcohols, in this study, a generalized new mechanism for chemical kinetic analysis of RP-3 aviation kerosene/low-carbon alcohol blended fuel was developed. Based on this blending mechanism, the ignition characteristics and chemical reaction kinetic analysis under different alcohol types and blending ratios were investigated. It was shown that at 1300 K, n-butanol could enhance the fuel oxidation most effectively, accelerating the peak time of O and OH radicals by nearly 12% and the peak time of the CH4 component by nearly 13% compared with that of ethanol. While the ethanol blending ratio of 30%, improved the peak rate of O, OH radicals by nearly 4%, the CH4 mole concentration peak enhancement was nearly 9%, proving that with the increase of the blending ratio, the rate of accumulation of reactive radicals increased, the reaction rate of the blended fuel was accelerated.