连续旋转爆震波细致结构及自持机理

Detailed structure and propagating mechanism research oncontinuous rotating detonation wave

关键词:  连续旋转爆震波  爆震波高度  稀疏波  自持机理

Key words:  Continuous rotating detonation wave  Height of detonation wave  Rarefaction waves  Propagating mechanism.

摘要:

基于化学非平衡流解耦方法和详细化学反应机理,在0.1mm的网格尺度下对连续旋转爆震波内流场和爆震波平掠惰性气体界面的传播过程进行了数值模拟。详细分析了连续旋转爆震波的空间结构,由于在出口侧无几何约束,受一系列稀疏波的影响,旋转爆震波强度受到不同程度的削弱,形状也发生了相应的变化。爆震波平掠惰性气体界面时的流场分布与连续旋转爆震波结构极为类似,对比研究了波前可燃气体层高度对爆震波结构和传播过程的影响,当爆震波高度较小时,其抵御惰性气体侧稀疏波衰减的能力弱,波阵面严重变形,爆震波解耦。若爆震波要稳定自持传播,其必须要达到一定的临界高度来抵御稀疏波的影响。

Abstract:

Based on a de-coupled solver of non-equilibrium reacting flow and detailed chemical reaction model, the flow field of continuous rotating detonation wave and propagating phenomena of detonation sweeping a contact surface of inert gas were calculated on 0.1mm grid scale. The spatial structure of continuous rotating detonation wave was analyzed. Due to the absence of geometric constraint at the side of oblique shock wave, the detonation wave was attenuated by a set of rarefaction waves. The bottom part of detonation wave was attenuated greatly, which makes it shaped like a curve. Flow field of detonation sweeping the inert gas contact surface was also detailed, which is identical to the structure of continuous rotating detonation wave. The influence of the height of detonation wave was analyzed. When the height of detonation wave is small, it could not resist the attenuation of rarefaction waves. The detonation front arced severely, leading to decoupling of the detonation wave. To propagate stably, the height of detonation wave must reach a critical value.