Study on variable geometry inlet of acceleration hypersonic vehicle

The variable geometry inlet used on acceleration hypersonic vehicles was designed. Containing movable cowl and ramps, the structure could realize variable geometry adjustment at Mach 4. The geometry has good restart characteristic and high flux coefficient. At the same time the compressed property is good at high speed. The inlet can work normally and efficiently between Mach 2.5 and Mach 8. The performance of the inlet was calculated. The results show that the configuration used in low mach number can't meet the compressed property requirement at high Mach number, while the configuration used in high Mach number can't satisfy the restart character and the flux coefficient is low at low speed. The fixed inlet can't fulfil the task requirement for the air-breathing vehicle working in wide speed. It's a tendency to adopt the variable geometry inlet.