脉冲爆轰推进装置中波过程的实验研究与分析

Experiment and Analysis on Wave Processes in Pulse Detonation Engines

研究了脉冲爆轰推进装置(PDE)中各种波的过程与相互作用,包括爆轰波的建立与传播、爆轰波后的Tay-lor稀疏波以及因开口处气流膨胀产生的反射稀疏波等.在实验中引入了预燃腔从而实现了氢气/空气混合气体的快速起爆.针对实验结果,采用CJ理论以及不带化学反应的多组分Euler方程对整个PDE装置的波运动过程进行了分析,其结果显示出口端反射稀疏波足以排出爆轰管内的爆轰产物,使爆轰管内的压力降低到较低的水平.最后给出了一定燃料/氧化剂的混合气体和初始压力下估算该PDE的推力性能以及最大可能的工作频率的方法.

Wave processes and interactions in pulse detonation engines are numerically and experimentally analyzed, including initiation and transmission of detonation wave, Taylor rarefaction wave generated after the detonation wave, and reflected rarefaction wave caused by the airflow expansion at the outlet. In the experiments, detonation is directly initiated in the air/hydrogen mixture by a pre-combustion chamber. The exhausting process is numerically simulated by multi-species Euler equations without chemical reactions. The detonation wave is calculated by CJ theory. The results show that the reflected rarefaction waves are strong enough to decrease the gas pressure at the closed end to a low level. The thrust property and utmost cycle frequencies of the PDE are analyzed.