# Construction of a Chemical Kinetic Mechanism of Five-Component Surrogate Fuel for RP-3 Kerosene
## 1 Introduction  
Over the past few decades, transportation and travel methods have undergone rapid development, with the aviation industry becoming an important mode. As the main fuel for aircraft engines, aviation kerosene undergoes complex turbulent motion and chemical reactions after entering the combustion chamber. It is difficult to directly obtain the combustion and flow field distribution characteristics inside the engine combustion chamber through experiments. Numerical simulation research centered on fuel chemical kinetic models can achieve the dynamic simulation of complex turbulent combustion processes. However, the combustion process of aviation kerosene also involves hundreds of intermediate species and thousands of elementary reactions. It is very difficult to construct a realistic and detailed fuel chemical kinetic model, and such models are difficult to directly apply in calculations [1, 2]. Therefore, a common approach is to use one or more components based on the physical and chemical properties of the actual fuel as a surrogate mixture for the actual fuel, and then construct a chemical reaction kinetic model of the surrogate fuel mixture to simulate the combustion process of the actual fuel [3]. Many scholars have conducted detailed research on the construction of surrogate fuels for Jet A-1, Jet-A, and JP-5 [4; 5; 6; 7]. And the number of components in the surrogate fuel mixtures has gradually increased, and aromatic hydrocarbons, cycloalkanes, and other substances have been gradually added from alkanes. The prediction effect of the mechanism on various parameters of real fuels has become increasingly accurate and comprehensive, but the corresponding chemical kinetic models have also gradually increased [8]. However, compared with Jet-A and JP-5, RP-3, which is widely used as civil aviation fuel in China, has relatively late research on its corresponding chemical kinetic models, but the corresponding research has also begun to increase in recent years [9]. [PERSON] [10] proposed a four-component fuel mechanism consisting of n-decane, n-dodecane, ethyl-cyclohexane, and p-xylene, which includes 168 species and 1089 reactions. Experimental results show that this model is basically consistent with the real RP-3 fuel in terms of laminar flame speed, but there is a gap with the experimental values in terms of ignition and combustion characteristics. [PERSON] [11] conducted a detailed analysis of surrogate models containing 1 to 10 species components and constructed a four-component surrogate model that can accurately predict the pseudo-critical temperature under supercritical pressure. [PERSON] [12] developed a two-component surrogate fuel model consisting of n-decane and n-propylbenzene and experimentally verified its accuracy in predicting laminar flame speed and ignition delay. [PERSON] [13], based on the fuel composition of RP-3, proposed a mechanism (toluene, trans-10-hexadecene, n-decane, isohexadecane) containing 231 species and 5591 reactions to match the physical and chemical properties as well as the kinetic characteristics of RP-3 kerosene. [PERSON] [14] constructed a five-component surrogate fuel model (n-decane, n-dodecane, isohexadecane, methylcyclohexane, toluene) based on the physical and chemical properties of RP-3 fuel. The low-temperature oxidation, ignition delay time, and laminar flame speed of the surrogate fuel were in very good agreement with those of RP-3 fuel. [PERSON] [15] improved the predictability of the adiabatic flame temperature of the RP-3 surrogate fuel model at high equivalence ratios by constructing a three-step simplified mechanism involving CO-C\({}_{2}\) and H\({}_{2}\)-H\({}_{2}\)O equilibria, with only a 9.3% increase in computational time. From the existing research, it can be seen that the current combustion kinetic models of RP-3 surrogate fuels still have problems such as large mechanism size and significant differences between the model's physicochemical properties and experimental data [15; 16].