宽速域变几何轴对称进气道结构设计及气动性能分析

A wide speed range variable geometry axisymmetric inlet with flight Mach number of 0~1.8 is de⁃ signed. The flow characteristics of the baseline axisymmetric inlet in the full speed range are analyzed. The opti⁃ mal operating conditions of different adjustment schemes and their effects on the flow characteristics and aerody⁃ namic performance of the inlet are studied. The results show that：1.2≤Ma≤1.8，the baseline axisymmetric inlet can meet the flow demand of the engine matching point ；when 0.8≤Ma<1.2，the addition of the bleed slot will in⁃ crease the low-energy fluid in the diffuser and reduce the effective flow area of the inlet. When Ma=0.8 and Ma= 1.0，the flow difference between the inlet outlet flow and the engine matching point before and after the bleed slot is closed decreases from 7.7% and 3.4% to 0.3% and 0.9%，respectively. When 0.5≤Ma<0.8，the backward mov⁃ ing center cone can reduce the total pressure distortion index of the inlet outlet. The total pressure distortion index of the inlet before and after the moving center cone is reduced by 1.4% and 3.1% at Ma=0.5 and Ma=0.6，respec⁃ tively. When 0<Ma<0.5，the addition of auxiliary inlet valve can not only meet the flow demand，but also improve the total pressure recovery coefficient and outlet flow field uniformity of the inlet.