可爆性气体爆炸极限和爆燃转变成爆轰的研究

我们成功地研制了长为6.6m、内径为100mm的柱形爆炸激波管。利用此激波管我们研究了氢气和氧气混合物的爆炸特性。研究表明:氢气和氧气混合物的可爆性极限为25％H2至84％H2（体积比）;混合物起爆的临界初始压力P0c近似与混合物的浓度无关。我们还用石英传感器技术测量了混合物从爆燃转变为爆轰的过程（DDT）,确定了爆炸速度、爆炸压力与混合物初始压力P0的关系。爆燃波速度D和压力P快速增加,并且DG0（声速）时,爆燃波能转变成爆轰。爆燃波速度D和压力P衰减时,爆燃波将熄灭。氢氧混合物浓度接近上限时,爆燃向爆轰转变时的爆轰呈过激励状态,然后逐渐趋于正常爆轰。C-J理论可近似预估气体爆轰参数。

STUDIES OF THE DETONABILITY LIMIT AND THE TRANSITION FROM DEFLAGRATION TO DETONATION FOR DETONABILITY GASES

The cylindrical explosion shock tube (6. 6m long, 100mm diameter) has been developed. The explosion behaviours of the mixture of hydrogen and oxygen are studied with the shock tube. The results show that the detonability limit for the mixture of hydro- gen and oxygen is in the range from 25%H2 to 84%H2(per-cent of volume);critical initial pressure poc of initiated mixture is approximately independent of the concentration for the mixture. The transition from deflagration to detonation is measured by means of quartz gauge technique; the relation of explosion velocity and explosion pressure with initial pressure P0 for the mixture are determined. when the deflagration velocity D (or pressure p) rapidly increases and D>C0 (sound Speed), it is possible to transit from the deflagration to detonation. When the deflagration velocity (or pressure) decreases, the deflagration will fail. As the concentration of the mixture of hydrogen and oxygen approachs to the dense limit, at first the transited detonation is an overdriven detonation, then it gradualiy fades to normal detonation. The parameters of gas detonation may be approximately predicted by the C-J theory.