Study On Combustion Reaction Mechanism Of Domestic Aviation Kerosene Multi-Component Surrogate Fuel

Aviation kerosene is the main fuel for aviation engines.It contains between 10 and 16 carbon atoms.It has dozens of components and is mainly classified into three types of compounds:paraffins,cycloalkanes,and aromatics.Through the analysis of the composition and properties of domestic RP-3 aviation kerosene,combined with the simulated surrogate fuel proposed by the predecessors,and based on the selection indicators such as the number of carbon atoms,the number of hydrogen atoms,the ratio of hydrogen to carbon,and the relative molecular mass,this paper proposes a four-component surrogate fuel about RP-3 which contains 41%n-dodecane,37%n-decane,3%n-propyl cyclohexane,and 19%n-propyl benzene in mole fraction.The chemical reaction kinetic models of the four components were constructed by applying the reaction path flow analysis method,sensitivity analysis method,and decoupling method,respectively.The comparison between the calculated results and the experimental results show that the four single-component reaction mechanisms can accurately predict the ignition delay times、the concentration trend of the fuels and products;at the same time and the laminar flame speed.A surrogate fuel mechanism that contains four-component surrogate fuel with 136 components and 308 reactions about RP-3 aviation kerosene is constructed by integrating the four-component mechanism.The ignition delay time and laminar flame speed are calculated by using the combustion reaction mechanism of aviation kerosene surrogate fuel,and the results are compared with the experiments.The results show that the ignition delay time calculated by the reaction mechanism at pressures of 1 and 2 atm,equivalence ratios of 0.5,1.0 and 1.5 are in good agreement with the experimental values.At pressure of 1 atm-3 atm,equivalence ratios of 0.8-1.4,temperatures of 420 K-480 K,the calculated laminar flame speed are coincident with the experimental data,and the peak values appear at equivalence ratio of 1.1.The comparison with the combustion characteristics of jet fuel jet-A and S-8,which are commonly used abroad,shows that the calculated results are in good agreement with the experimental results.The four-component simulation surrogate fuel reaction kinetics mechanism proposed in this paper has good calculation results in a wide range of operating conditions,and can well show the ignition and combustion characteristics of domestic aviation kerosene.It provides a solid support for the numerical calculation of the thermal performance of the combustion chamber coupled with the fuel reaction.