带二次流增推尾喷管的脉冲爆震发动机数值模拟研究

Numerical Simulation of Pulse Detonation Engine(PDE)with Fluidic Nozzle

为提升现有脉冲爆震发动机增推喷管性能,对带二次流尾喷管发动机分别在定常流和爆震多循环过程进行了数值模拟,研究了二次流尾喷管的流场并计算了其推进性能。结果表明,定常流动中,随着主流压力的升高,注入二次流对尾喷管推进性能的提升幅度逐渐降低;当爆震室内压力很高时,二次流的瞬时流量会自动降低或者停止注入,当爆震室压力较低时,二次流流量又会自动恢复;单管注入二次流对PDE平均推力和平均单位推力的提升率分别达到2.63%和0.36%;双管注入二次流达到5.96%和0.75%。

In order to increase the nozzle＇ s propulsion performance of PDE,numerical studies of fluidic nozzles have been carried out to study the flow field and the propulsion performance of fluidic nozzles in steady flow and during the cyclic operation. Simulation results and their analysis show preliminarily that：（1） in steady flow,with the use of secondary injection,when the core flow＇s pressure increases,the augmented ratio of the nozzle＇s propulsion performance will decrease;（2） when the detonation chamber＇s pressure is very high,the instantaneous flow rate of the secondary flow will dynamically reduce or stop injecting;（3） when the detonation chamber＇s pressure is low,the secondary flow will dynamically restore. The augmented ratio of average thrust and that of specific average thrust with single injector are respectively 2. 63%,0. 36%,and 5. 96%,0. 75% with dual injector.