当量比和间隙尺寸对爆震波传播过程的影响

为探索微型脉冲爆震发动机推进系统的可行性,进行了微空间内爆震极限特性的研究.通过对预混氢气/氧气爆震火焰在平板狭缝中的传播过程进行测量,分析了爆震波压力、速度随当量比和间隙尺寸的变化趋势,发现在极限范围外,来自稳流段的爆震波都能在间隙内通过压力和速度的自我调整后达到稳定状态,调整过程所需的距离随间隙尺寸减小而增长.根据爆震波速度衰减的定义,给出了激波和火焰锋面速度沿间隙通道方向的变化特点,观察到了微尺寸下爆震波的4种传播模式:稳定爆震波、准稳定爆震波、低速爆震波和非爆震波. 

Effects of equivalence ratio and gap size on the propagation behavior of detonations

To explore the feasibility of micro-scale pulse detonation engine propulsion system,detonation limits in narrow channels have been investigated.By observing and measuring the propagation behavior of premixed hydrogen-oxygen detonation flames in narrow gaps,effects of gap size and equivalence ratio on detonation wave pressure and velocity were experimentally analyzed.Outside the detonation limit,the detonation wave coming from the guide section can reach a steady state in the gap by self-adjustment of the pressure and velocity.The distance required by the adjustment process was growing when the gap size decreased.According to the definition of velocity deficit,the characteristics of the velocities of shock and flame front along the micro-channel were summarized,and four propagation models-steady detonation,sub-steady detonation,low-speed detonation and non-detonation were observed.