H2/Air连续旋转爆震波的起爆及传播过程试验

Experiment on the Ignition and Propagation Processes of H2/Air Continuous Rotating Detonation Wave

关键词:  连续旋转爆震波  H₂/Air组合  喷注方式  试验研究

Key words:  Continuous rotating detonation wave  H₂/Air mixture  Injection method  Experimental research

摘要:

在环缝-喷孔对撞式喷注模型发动机上,采用H₂/O₂热射流切向喷注的起爆方式,进行了H₂/Air组合的连续旋转爆震试验,试验成功起爆并实现了爆震波的持续旋转传播。切向喷注的热射流并没有直接诱导形成旋转爆震波,从点火到形成稳定传播的旋转爆震波之间存在时间间隔。对高频信号的时频分析结果表明,在该试验工况下,旋转爆震波的传播过程非常稳定,其传播频率为5.5~5.95 kHz,平均传播频率为5.75 kHz,对应的平均传播速度为1716.4m/s,为理论预测值的91.14%。在没有测量高频压力的情况下开展了长程试验,结果表明,连续旋转爆震波也可以在更长的时间范围内稳定工作。 

Abstract:

Based on the engine model with slot-injector impinging injection method, H₂/Air continuous rotating detonation was studied experimentally. The engine was ignited by tangentially installed H₂/O2 hotshot tube. But the H₂/O2 hotshot jet could not induce the rotating detonation wave directly. There was a delay time between the ignition and the start of continuous rotating detonation wave. Time-frequency characteristic of the signal measured by fast frequency pressure sensor was analyzed. Under this experiment condition, the rotating detonation wave propagation process was stable. Its propagation frequency ranged 5.5~5.95kHz, and the mean propagation frequency was about 5.75kHz, with the corresponding mean rotating velocity of 1716.4 m/s, which was 91.14 percent of the theoretical CJ velocity value. Long-time test without fast frequency pressure sensor was carried out, and the results demonstrated that the rotating detonation wave could also propagate continuously for a long time on this engine model.