扩张管内爆轰波临界传播特性的研究

Study on Propagation of Detonation Wave Travelling in Divergent Tube Under Critical Condition

假设重点火位置沿扩张管内扰动区的最后一道特征线，结合描述爆轰波绕射后重点火产生的特征量Ｍ／ｙｓ与沿胞格长度方向诱导激波与化学反应区分离时爆轰波阵面衰减的速度梯度△ＭＣＪ／Ｌｃ，本文得到了临界条件下扩张管内爆轰波维持传播而不熄灭的重点火准则。利用Ｗｈｉｔｈａｍ的激波线射理论，由重点火准则导出了任意扩张管角度下爆轰波胞格尺寸的计算公式。计算结果与实验结果相比，二者不仅趋势一致，而且量值也很接近。

When re-ignition position was assumed along last characterized line in distributed zone of divergent tube, the re-ignition criteria of detonation wave propagating through divergent tube under critical condition was got in this paper, whenever the characterized velocity gradient M/y describing reignition was related to the parameter △MCJ/Lc describing seperation of induced shock and reaction zone.By use of Whitham shock dynamics, the formula of predicting cell size at arbitray divergent angle was obtained from re-ignition criteria. The computed values of cell size are in good agreement with experimental ones not only in curve trend, but also in magnitude.