点火位置对圆盘结构下旋转爆震波起爆过程的影响

Effects of Ignition Position on Initiation Process of Rotating Detonation Wave in Plane-Radial Structure

为分析点火位置改变对旋转爆震波(RDW)起爆过程的影响,在圆盘形旋转爆震发动机上进行点火实验,研究了不同点火位置、质量流率条件下旋转爆震波的建立过程及工作特性。结果表明,不同点火位置下,RDW的起爆过程皆经历点火器放电、爆燃转爆震以及稳定旋转爆震3个阶段。点火位置靠近喷注面附近时,RDW起爆过程中的无序缓燃模式缩短,起爆时间缩短,且一致性更好。在燃烧室出口位置点火,低质量流率条件下,RDW的起爆时间明显延长;质量流率小幅度提高有效缩短了RDW的起爆时间,而质量流率大幅度提高增加了RDW起爆过程的波头数。模态转变的临界条件附近,点火位置改变可能会影响RDW起爆段的工作模态,在燃烧室中心位置附近点火,更容易得到多波旋转爆震波。点火位置改变对旋转爆震发动机(RDE)稳定段的工作模态和爆震波参数影响很小。

A plane-radial rotating detonation engine was tested to identify the effects of ignition position on the initiation process of rotating detonation wave,and the RDW establishment processes and operating characteristics under different ignition positions and mass flow rates were investigated.The results show that the RDW’s initiation process undergoes three phases:igniter discharge,deflagration to detonation transition and stable rotating detonation.When the ignition position is near the injection surface,the disordered deflagration mode is shortened,and RDW’s initiation time decreases with better uniformity.When the ignition position is at the combustor exit,the RDW’s initiation time increases obviously under the condition of low mass flow rate.A small increase of mass flow rate effectively shortens the RDW’s initiation time,while a significant increase of mass flow rate greatly increases the number of waves in the RDW’s initiation process.Under the critical condition of mode transition,changing the ignition position may affect the RDW’s initiation mode.When the ignition position is near the center of combustor,it is easy to obtain multi-wave rotating detonation,but changing the ignition position has little effect on the RDE operating mode and detonation-wave parameters in the stable operating process.