Hypersonic Combustion by Standing Detonation Using Counter-Supersonic Flow

1.延长现有爆震驱动激波风洞的低压段，使试验时间从0.7ms延长到2.0ms，但喷管出口静压降低了20%。2.OH消光测量表明，未被驱动气体污染的超音速气流持续时间约为0.5ms，远小于理论值5ms。3.采用在高压段和低压段分别引入氦和氢的激波管，可以产生静压70kpa，静温度600K的可燃超音速气流。在垂直于可燃超音速流动方向引入爆轰的情况下，发现绕射波阵面解耦为激波和反应阵面。试验段底部激波前锋反射后，爆轰重新启动，并在上游和下游传播。5.超音速流动中爆轰的表观速度在上游区域比CJ速度快，在下游比CJ速度慢。6.烟箔记录表明，泡状结构沿超音速方向发生变形。池的纵横比实验值与基于CJ速度、横波速度和超音速流动速度的计算值吻合较好。

1.Extension of the low pressure section of the present detonation driven shock tunnel resulted in longer test time from 0.7 ms to 2.0 ms, although static pressure at the nozzle exit decreases by 20 %.2.OH extinction measurement revealed that duration of supersonic air flow which is not contaminated by the driver gas is about 0.5 ms, which is much less than the theoretical value of 5 ms.3.By using the shock tube in which helium and oxyhydrogen are initially introduced in the high pressure and low pressure section, respectively, it was possible to generate a combustible supersonic flow with static pressure of 70 kPa, static temperature of 600 K, and mach number of 1.2 without spontaneous ignition of the mixture.4.In the case that detonation is introduced perpendicularly to the direction of the combustible supersonic flow, it was found that the diffracted wave front is decoupled into a shock and reaction front. After reflection of the shock front at the bottom surface of the test section, detonation is re-initiated and then propagates upstream and downstream.5.Apparent velocity of detonation in a supersonic flow is faster in the upstream area and slower in the downstream than CJ-velocity by speed of the supersonic flow.6.Smoked foil record shows that cellular structure is deformed in the direction of the supersonic flow. Experimental value of the aspect ration of the cell agrees well with the calculated one based on the CJ-velocity, the velocity of the transverse wave, and the speed of the supersonic flow.