旋转爆震发动机工作特性试验研究

为研究旋转爆震发动机的工作特性,在以H_2/air为推进剂的发动机模型上进行试验,利用离子探针和高频压力传感器分别采集火焰信号和压力信号,改变空气质量流量,分析并对比了高、低质量流量下发动机的点火、稳定传播及熄火过程中火焰和压力波的变化情况。结果表明:火焰与压力波的主频相同,是耦合传播的,传播速度可达1 660 m/s;对于低质量流量(75.37 g/s),靠近燃烧室入口的离子探针的离子信号峰值大于远离燃烧室入口的离子信号峰值;对于高质量流量(102.125 g/s),远离燃烧室入口的离子探针的离子信号峰值大于较近点的离子信号峰值;新鲜反应物填充对靠近燃烧室入口的点的作用时间长于较远的点;压力信号瞬时频率的相对标准差小于火焰信号;小流量的点火时间短于大流量;切断H_2供给后火焰比压力波更早熄灭。

Experimental Study on Operating Characteristics of Rotating Detonation Engine

Experiments on rotating detonation engine( RDE) with the propellant of H2/air were conducted to investigate the operating characteristics of engine. Ion probes and high-frequency pressure transducer were installed simultaneously to measure flame signal and pressure signal respectively. By changing air mass-flow-rate,the flame and pressure wave signals of the ignition process, stable stage and shut down process were analyzed under the high and low mass-flow-rate. The dominant frequency of flame is the same as that of pressure wave, and they are coupling during propagation, and the propagation velocity reaches 1660 m/s. When mass flow rate is low(75. 37 g/s),the flame signal peaks at the point near the inlet of combustion chamber, are larger than that at the further point. When mass flow rate is high (102. 125 g/s),the flame signal peaks at the further point are larger than that at the closer point. The fresh gas injection has more time-wise effect on the closer point than the further one. The relative standard deviation of instantaneous frequency of pressure signal is smaller than that of the flame signals. Furthermore,the ignition time under the conditions of lower mass flow rate is shorter than that under the conditions of the higher mass flow rate. When the supply of H2 is cut off,the flame disappears earlier than pressure wave.