Research on the Cooling Characteristics of the Circular Ring Structure of Aircraft Engine Endoscope Probes

Aircraft engine endoscope probes often face difficulties in effectively detecting internal structures in high-temperature environments. In order to improve the thermal protection characteristics of endoscope probes, this paper designs a probe-cooling structure with a circular ring pressure drop structure and calculates and analyzes the cooling effect of the probe under different gas cooling conditions. Study the influence of size parameters and cooling medium properties of the structure on the cooling characteristics of the probe, analyze the temperature distribution of the probe mirror, cooling efficiency distribution, and cold flow outlet flow distribution. The results show that the larger the outlet width of the annular cooling structure, the better the cooling effect, and the optimal cooling effect structure is 0.7 mm; the larger the opening angle, the lower and then the higher the temperature of the endoscope probe surface, and the best cooling effect occurs when the optimal angle is 40°; the larger the proportion of mixed liquid nitrogen, the lower the temperature of the probe mirror surface. A 5% proportion of mixed liquid nitrogen can reduce the temperature of the probe mirror surface by about 11 K.