变截面引射器轴向位置对脉冲爆震火箭发动机的性能影响

Effect of Axial Position of Ejectors with Variable Cross-Section Area on Performance of a Pulse Detonation Rocket Engine

在5～15Hz工作频率下,以煤油为燃料,氧气为氧化剂,当量比为1.0的条件下,对不同轴向位置处变截面引射器的增推性能进行了实验研究。通过试验,获得不同安装位置时PDRE的推力。研究表明,引射器轴向安装位置对增推性能有很大影响。扩张型引射器适宜安装在PDRE射流出口下游2～3倍射流出口直径处,最大推力增益为102.57%;收敛型引射器适宜安装在上游一倍射流出口半径处,最大推力增益为86.7%。实验中,所有轴向安装位置都可产生正推力增益。

The thrust augmentation was experimentally investigated for ejector axial position with variable cross-section ar- ea, using kerosene as fuel and oxygen as oxidizer at the equivalence ratio 1.0 and the working frequency from 5Hz to 15Hz. Ejector includes the diverging ejector and the converging ejeetor. The results show that the thrust augmentation is influenced largely by ejector axial position. Divergent ejector fixed downstream has a greater thrust augmentation which ean be about 102.57%. However, the thrust augmentation of convergent ejector has the contrary rule whose maximum value can reach 86. 7%. Ejectors with variable cross-section area can provide positive thrust augmentation whether it is fixed downstream or upstream.