初始条件对管道内爆轰波传播特性影响研究

Effect of Initial Conditions on Propagation of Detonation Wave in Round Tube

实验研究了C_2H_2+2.5O_2+nAr气体爆轰波传播特性随初始条件变化规律。采用光电二极管测量爆轰波传播速度,烟迹法记录爆轰波胞格结构。结果表明:随初始压力降低,爆轰波在管道内出现稳态式、快速波动式、失效式传播模式。稳态式传播时爆轰速度局部波动小于平均速度的5%,初始压力对爆轰速度几乎无影响;快速波动式传播时爆轰速度局部波动增大,平均速度发生衰减,衰减幅度随初始压力降低而增大。随Ar稀释浓度增加,爆轰速度逐渐减小,且Ar稀释浓度对爆轰速度的影响显著。胞格尺寸随初始压力的降低而增大;稳态气体胞格结构规整;而非稳态气体胞格结构杂乱。

The propagation characteristics of C2H2 ＋2. 5 0 2 ＋ nAr gaseous detonation wave with the variation of initial conditions are investigated. The photo diode was used to measure the local velocity of the detonation wave, and the smoked foils were used to register the cellular structure of detonation wave. The experimental results show that the detonation wave is stable mode, rapid fluctuation mode and failure mode in the tube with the decrease of in-itial pressure. The fluctuations of local velocity of stable detonation is less than 5 % of the averaged velocity, and the initial pressure has little influences of detonation velocity; The fluctuations of local velocity of rapid fluctuation detonation increase with the decrease of initial pressure, the averaged velocity reduces , and the attenuation decrea-ses with the initial pressure increasing. The detonation velocity decreases with the increase of argon dilution concen-tration ,and the effect of argon dilution concentration on the detonation velocity is significant. The cellular structure size increases with the decrease of initial pres sure, and the cellular structure of the steady state gas is regular.