多孔火药填充床中燃烧转爆轰(DDT)的模拟与分析

随着火炮装药装填密度的提高和火箭推进剂中硝胺组份的增加,它们的总体性能虽有改善,但同时使燃烧转爆轰的感度也加大。在一定条件下,粒状高能固体火药填充床中,将出现DDT现象。本文着重研究燃烧转爆轰前的过程。描述DDT过程的两相反应流体动力学模型用MacCormack有限差分格式求解,得到的转爆距离和爆轰速度与试验观察结果符合得很好。计算表明,粒状药床中的两种转变机制似乎是可以相互转化的。

MODELING OF DEFLAGRATION-TO-DETONATION TRANSITION (DDT) IN POROUS PROPELLANT BEDS

With decreasing the porosity of charge beds in guns and increasing niframine content of solid propellants in rockets, the overall performance of these systems is improved, except that the sensitivity of deflagration-to-detonation transition (DDT) is strengthened. Under certain conditions, DDT can occur in the high-energy granulated solid propellant beds. The emphasis of this paper is on the transient event prior to detonation. A reactive two-phase flow model of this phenomenon is established and solved with the MaClormark finite difference scheme. The detonation run-up distance and the detonation velocity predicted by computation were in good agreement with the experimental observations. The calculated results show that the two kinds of transition mechanism of granular solid propellant beds appear to be changeable from one to another.