Morphing Supersonic Inlet with Deforming Air Cell

Abstract

A mixed-compression supersonic inlet with a variable throat can solve the contradiction of the starting capability at low Mach numbers and the total pressure recovery performance at high Mach numbers. However, the variation of the throat area is rather difficult for an axisymmetric supersonic inlet. A new method based on a deforming air cell to control the throat area of an axisymmetric inlet is brought forward and investigated by both experimental and computational methods. The morphing behavior of the deforming air cell in a supersonic wind tunnel is also obtained. The results indicate that the contraction ratio of the inlet can be effectively controlled by the cooperation of the air cell profile under different charging pressures and the cowl inner surface. As compared with a fixed geometry inlet, the total pressure recovery and the corresponding maximum backpressure of the morphing inlet are increased by 25.7 and 31.8%, respectively. In addition, the air cell can withstand the impact of strong oscillatory flows when the inlet experiences buzz.