Expansion ignition limit of hydrocarbon fuels based on the controllable free radical relay combustion under extreme conditions
Controllable hydrocarbon fuel combustion and combustion path adjustment are effective but difficult approaches to achieve reliable ignition under extreme conditions. However, the effective mechanism to control the combustion characteristics of hydrocarbon fuels is still unclear. In this study, the fuel (Fuel 6) based on free radical relay combustion (FRRC) significantly expands the ambient temperature-based ignition limits of pure fuel and shows a weak temperature correlation with ignition delay time. In addition, Fuel 6 still has a 100 % ignition probability at 50 kPa (the corresponding ignition limit flight altitude increased from 0.9 km above sea level to 5.4 km). Gaussian simulations show the thermodynamic feasibility of FRRC and prove the relay effect. According to kinetic analysis , the combustion reactions can be adjusted based on FRRC and exhibit three types of oxidation reactions, of which the reaction activation energies are all lower than those of the oxidation reactions of pure fuel. Furthermore, the results of in-situ Fourier transform infrared spectroscopy are consistent with the kinetic analysis based on thermogravimetric and differential thermogravimetric studies. The investigation of the combustion control mechanism under extreme conditions helps to broaden the ignition limit of the aviation engine combustor and to significantly improve the accurate control level of ignition under extreme conditions, providing theoretical support for solving the ignition problems of advanced aviation engines under extreme conditions.
危险品化学品经营许可证（带存储）