气体爆轰波在声学吸收壁下游的再加强过程  

The Re-intension Process of Gaseous Detonation Downstream of the acoustic Absorbing Walled Section

作　　者：年伟民[1] 周凯元[1] 王汉良[1] 叶剑飞[1] 夏昌敬[1] 

机构地区：[1]中国科学技术大学力学与机械工程系,合肥230027

出　　处：《实验力学》2005年第1期37-43,共7页Journal of Experimental Mechanics

摘　　要：实验研究了爆轰波在声学吸收段下游发生的再恢复过程.利用声学吸收段首先将一个稳定的爆轰波衰减,于是产生一个非稳定爆轰波,速度降为45%～60%DCJ.该非稳定爆轰波传出声学吸收段后再次加强,并在距声学吸收段出口端一定距离处突然发展成超驱动爆轰.实验利用烟迹技术捕捉了爆轰波从发生衰减到再次加强的全过程,获得了爆轰波再加强距离随初压变化的实验规律.由此,本文建立了再加强段内加速传播火焰的理论模型,称为激波-爆燃波复合态,并解释了火焰加速和超驱动爆轰形成的机理.An experimental investigation is presented concerning the re-intension process of a detonation wave occurring downstream of the acoustic absorbing walled section in this paper. Firstly, a steady gaseous detonation wave is attenuated by the acoustic absorbing walls, and hence an unsteady detonation wave come into being, with the speed dropped to 45%～60%D\-(CJ). And then the re-intension of a detonation wave takes place downstream of the acoustic absorbing walled section, accompanying with the onset of an overdriven detonation at some distance away from the exit of the acoustic absorbing walled section. In experiments, an entire process from occurrence of the attenuation to the onset of the overdriven detonation is captured by using smoked foil records and the experimental relationships between the re-intension length and the initial pressure are also got. Consequently, the theoretical model for the accelerating flame in the re-intension process is developed, called shock-flame complex. Furthermore the mechanism of the flame acceleration and the onset of an overdriven detonation are discussed.

关 键 词：爆轰波 声学吸收壁 下游 气体 恢复过程 实验研究 实验规律 理论模型 火焰加速 非稳定 波衰减 速度降 出口端 全过程 复合态 爆燃波 驱动 距离 激波 

分 类 号：O381[理学—流体力学] U173.2[理学—力学]