当前位置: X-MOL 学术Propellants Explos. Pyrotech. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Feasibility of Detonation in Porous Silicon Nanoenergetics
Propellants, Explosives, Pyrotechnics ( IF 1.8 ) Pub Date : 2021-05-28 , DOI: 10.1002/prep.202000311
Philip M. Guerieri 1 , Brian Fuchs 2 , Wayne A. Churaman 1
Affiliation  

Porous silicon with sodium perchlorate oxidizer is hypothesized to be a detonable explosive, which is atypical for heterogenous fuel/oxidizer composites. The existence of detonation in energetic porous silicon remains contested and would theoretically feature several unique behaviors illustrated by this study. Calculations to predict detonation performance are performed using CHEETAH thermochemical code for silicon porosities of 45–85 % surrounding 69 %, which represents an experimentally typical case. Uniquely, e-PS detonation is predicted to produce low gas volume. At 69 % porosity, condensed detonation products comprise 78 % of the mass (varying from 86 % to 46 % for 45–85 % porosity), and therefore a low TNT equivalent mechanical energy of 0.429 (but 1.32 when comparing total detonation energy). The calculated pressure of detonation for 69 % porosity is 1.065 GPa, only about 4 % of that of typical military explosives but over 50 times greater than compression wave amplitudes estimated for fast-burning nanothermites, which are comparable heterogenous fuel/oxidizer composites. At porosities above 67 %, computed detonation velocities are shown to exceed estimates for the unreacted speed of sound and therefore a detonation structure consistent with classical CJ theory is proposed. Indeed, published maximum experimental propagation speeds for energetic porous silicon in this upper porosity range when pore size is optimal agree well with CHEETAH computations of detonation velocity, thereby supporting that detonation is possible. Below 66 % porosity, sound speed in unreacted material overtakes the calculated detonation velocities. Traditionally this precludes formation of a detonation wave since the shockwave would decay as energy propagates ahead acoustically into unreacted material. However, experimental agreement is still observed between 60–67 % porosity. By comparing computed detonation pressure with estimates for the strength of unreacted porous silicon, this range is proposed to be a transition zone in which a detonation-like structure could be maintained, despite the inverted sound speed comparison, by rapid catastrophic fracture of porous silicon at the detonation front. This hypothesis implies that a sonic precompression wave must precede the detonation wave since at least a minor fraction of shock energy would propagate ahead in unreacted material. Finally, comparisons are made with baseline primary explosives and nanothermites showing that among metal-based composite energetics on the basis of reaction rate and detonation pressure, energetic porous silicon currently exhibits the most promise for replacing primary explosives at reasonable densities in igniters and augmenting initiator formulations.

中文翻译:

多孔硅纳米能学中爆炸的可行性

带有高氯酸钠氧化剂的多孔硅被假设为可爆炸药,这对于异质燃料/氧化剂复合材料来说是不典型的。高能多孔硅中爆炸的存在仍然存在争议,并且理论上具有本研究说明的几种独特行为。使用 CHEETAH 热化学代码对 45-85% 周围 69% 的硅孔隙率进行预测爆轰性能的计算,这代表了一个典型的实验案例。独特的是,e-PS 爆炸预计会产生低气体量。在 69% 的孔隙率下,凝聚的爆震产物占质量的 78%(对于 45-85% 的孔隙率,从 86% 到 46% 不等),因此 TNT 等效机械能低至 0.429(但在比较总爆震能时为 1.32)。69% 孔隙率的计算爆轰压力为 1.065 GPa,仅为典型军用炸药的约 4%,但比快速燃烧的纳米铝热剂估计的压缩波振幅大 50 倍以上,这是可比的异质燃料/氧化剂复合材料。当孔隙率高于 67% 时,计算出的爆轰速度超过了未反应声速的估计值,因此提出了与经典 CJ 理论一致的爆轰结构。事实上,当孔径为最佳时,已发表的高能多孔硅在该孔隙率上限范围内的最大实验传播速度与爆轰速度的 CHEETAH 计算非常吻合,从而支持爆轰是可能的。孔隙率低于 66%,未反应材料中的声速超过计算的爆速。传统上,这会阻止爆震波的形成,因为随着能量以声学方式向前传播到未反应的材料中,冲击波会衰减。然而,在 60-67% 的孔隙率之间仍观察到实验一致性。通过将计算出的爆震压力与未反应多孔硅的强度估计值进行比较,该范围被认为是一个过渡区,尽管声速比较倒置,但通过多孔硅在爆炸前沿。这个假设意味着声波预压缩波必须先于爆震波,因为至少有一小部分冲击能量会在未反应的材料中向前传播。最后,
更新日期:2021-05-28
down
wechat
bug