Study on the dynamic characteristics of thermal oxidation deposition of aviation kerosene under supercritical pressure

Abstract

Thermal oxidation deposition of aviation kerosene has a significant impact on the long-term operation of aircraft. In this study, a two-dimensional axisymmetric numerical model incorporating a pseudo-detailed chemical kinetic model of thermal oxidation deposition was developed based on dynamic mesh technology, and a 30-hour transient simulation of the thermal oxidation deposition process of supercritical aviation kerosene was conducted. The dynamic characteristics of the thermal oxidation deposition are examined and the effect of dissolved oxygen concentration is analyzed. According to the results, the large temperature gradient at the inlet and the higher temperatures in the second half of the channel encourage the thermal oxidation and surface deposition reactions to proceed rapidly. And it is found that the surface deposition rate decreases with increasing heating time. Both temperature and concentration determine the rate of dissolved oxygen consumption. The surface deposition rate increased by 195.33 % as the dissolved oxygen concentration increased from 10 to 40 ppm. In addition, the entry of aviation kerosene into the pseudo-critical region can indirectly reduce the rate of thermal oxidation surface deposition. This study is a guide to predict and inhibit the thermal oxidation deposition of aviation kerosene, improving the structural design of the regenerative cooling channel, and ensuring aircraft safety.