冷却流量偏差对超燃冲压发动机飞行速域影响

The influence of hydrocarbon fuel flow deviation on the allowable Mach number upper limit of scramjet was focused and researched. A quasi-one-dimensional coupling model of combustion and cooling was established and verified as an overall analysis tool. The simulation results showed that the working range of scramjet was seriously affected by the flow deviation. Taking the flow deviation β=–0.5 as an example,the flow deviation lowered the upper limit of the engine flight Mach number from Mа=6 to Mа=5,indicating that the flow deviation seriously restrained the safe operating speed range of the engine and affected the flight mission. The influencing mechanism of different combustion and cooling designs on the upper Mach number limit was compared and analyzed,such as counter flow cooling,multi-stage fuel injection, flow deviation initial position, and maximum wall/fuel temperature. The flow deviation was suppressed and the flight Mach number range was broadened. Finally,based on the experimental data of the cascade-throttle flow deviation suppression method,the upper flight Mach number limit of the engine was extended by 1 Mach number.