Experimental and Numerical Research on a Three-Dimensional Inward-Turning Inlet

AbstractThe aerodynamic performance and flow field structure of an inward-turning inlet at a high flying Mach number are attracting more and more attention. The main purpose of this paper is to study the aerodynamic performance and the back pressure characteristics of a circular entrance three-dimensional inward-turning inlet at Ma=5.0–8.0, with the combination of wind tunnel test and numerical simulation. This series of experiments is divided into three parts to explore the unstart boundary, self-start ability, and suction slots influence. The experimental results show that at design point Ma=6.0, the inlet outlet Mach number is 2.29 and the total pressure recovery coefficient is 0.31. Further numerical simulation results indicate that the opening of suction slots could enhance the maximum capability of back pressure about 7.3%. The circumferential flow in the isolator caused the asymmetry of the shock train and led to the nonuniform distribution of the separation region. The different size of the separation zones on the upper wall and the lower wall eventually leads to different pressure distribution.