【摘要】 讨论的激波管由氢氧前向爆轰产生高压驱动气体、并配有收缩截面段,它能产生高焓超高速气流.对此进行了模拟.既对变截面角度的作用,两端截面积比的作用又对比正向反向爆轰有何不同效果做了探讨.正向爆轰时主膜处的收缩段产生的汇聚作用既加强主激波又产生反向激波,缓解了爆轰波阵面后紧跟着的稀疏波导致主激波衰减偏快的不利影响.当收缩角度在30°和45°之间时,主激波的强度较高,衰减较小;当β接近90°时在主激波传播过一小段距离之后,主激波后高温高速气流较均匀,且主激波的衰减最小,具有实用价值.驱动段与被驱动段的截面积比越大,主激波的强度越高,但是最初阶段衰减也越快.反向爆轰时产生的主激波衰减最缓,但是同样的主激波强度需要的驱动段与被驱动段初始压力比前向爆轰高1个量级.更多还原

【Abstract】 The numerical simulation of variable cross-section shock tube driven by hydrogen oxygen forward detonation, which can produce high enthalpy and high speed flow, is studied. The influences of apex angle, cross sectional area ratio of driver tube to driven tube, and difference between forward and backward detonation are discussed. In the forward detonation case, the conical contraction can make use of concentration of energy to not only strengthen incident shock wave but also produce a reflection shock wave, which can weaken the negative effects of rapid attenuation of the incident shock wave caused by the tightly followed rarefaction wave. When the apex angle β is between 30°and 45°, the incident shock wave is stronger and attenuats less than the other situations. When β is near 90°and after the incident shock wave passes away from diaphragm for some little distance, the incident shock wave attenuats least and the following high temperature and high speed flow is uniform, thus there is an important practical value of this type of shock tube. The incident shock wave produced by detonation driver with large cross sectional area is stronger but attenuats faster at the beginning than that by the small. The incident shock wave produced by the backward detonation attenuats very slowly. But for the same Mach number, the required initial pressure of the detonable mixture for the backward detonation driver is higher than that for the forword detonation driver by nearly one order of magnitude.更多还原