An experimental and modeling study of oxidation of real RP-3 aviation kerosene. (1st December 2021) - Du, Li-Jun
Highlights: Atmospheric oxidation of real RP-3 aviation kerosene was investigated in a jet-stirred reactor (JSR) at φ=2.0 and 575–1100 K. The inlet fuels exhibit negative temperature coefficient behaviors. Bimodal curves of mole fraction curves of C2 –C4 hydrocarbons and aromatic species and oxygenates were observed. Within 600–800 K, alkanes are the most active components to produce H/OH/HO2 radicals to initiate the oxidation of aromatics and cycloalkanes. Sensitivity analysis demonstrates that the consumptions of both 1, 3, 5-trimethylcyclohexane and N-propylbenzene are promoted by H/OH/HO2 radicals. Abstract: The major components of a real Chinese RP-3 aviation kerosene were measured as 64.15% alkanes, 18.48% cycloalkanes, 15.88% aromatics. The oxidation of real Chinese RP-3 aviation kerosene was investigated in a jet-stirred reactor (JSR) at atmospheric pressure, φ = 2.0, and temperatures ranging from 575 to 1100 K. Mole fraction profiles of 25 species were detected with online GC and GC/MS. Three components (3C) surrogate fuel was validated against the measured results, as well as a detailed kinetic reaction model involving 453 species and 2991 reactions, was validated against the oxidation data A negative temperature coefficient (NTC) behavior of intermediates except for methane (CH4 ) was observed, due to the low-temperature activity of alkanes. The bimodal curves were observed for light hydrocarbons (C2 -C4 ) and aromatic species and oxygenate, in which the second one is generally larger than the first one for light hydrocarbons (C2 -C4 ) and aromatic species, while oxygenates exhibit adverse tendencies. Rate-of-production (ROP) analysis reveals that 1, 3, 5-trimethyl cyclohexane (T135MCH) mostly generates XCH2 D35MCH radicals by dehydrogenation reaction, isomerizes to CH3 SXD35MCH radicals, and further convert to C3 H6 . N-propylbenzene (NPB) is mainly dehydrogenated to form A1CHCH2 CH3 and A1CH2 CHCH3 radicals, which further transform to styrene (C6 H5 C2 H3 ). Sensitivity analysis demonstrates that the consumption of both T135MCH and NPB are promoted by H/OH/HO2 radicals at low temperatures. At a temperature higher than 900 K, an insufficient supply of H/OH/HO2 radicals may lead to a competing reaction between the three components. Within the temperature range of 600 to 800 K, n-dodecane is the most active component to produce H/OH/HO2 radicals to initiate the oxidation of NPB and T135MCH. These results could improve the understanding of the specific combustion process of RP-3 aviation kerosene, and help the establishment of RP-3 aviation kerosene surrogate fuel as well.