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71.
72.
爆轰产物物态方程及CHBr3相变的理论研究 总被引:4,自引:0,他引:4
由吉布斯自由能最小计算处于化学平衡状态的气体和固体混合系统的平衡组分。以BKW和VLW作为爆轰产物的物态方程对几种炸药爆轰参数作了预言,计算结果与实验值吻合得非常好。另外,还对CHBr3的冲击压缩分解作了化学平衡计算,给出了冲击压缩曲线,对文献[6]中提出的CHBr3在55~60 GPa存在相变的看法提出了质疑。 相似文献
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S. B. Dorofeev V. P. Sidorov M. S. Kuznetsov A. E. Dvoinishnikov V. I. Alekseev A. A. Efimenko 《Shock Waves》1996,6(1):21-28
Large scale experiments were carried out to study the effect of fuel concentration on air blast parameters and heat radiation
from gaseous detonations. Hemispheric plastic envelope (4 meters in radius) was used with propane-air mixtures containing
from 4 to 7 vol. % of fuel. The expressions for overpressures and impulses were determined in Sachs variables. The effect
of fuel concentration on blast parameters is shown to be insignificant for the same amount of oxygen in the mixture volume.
Thus the blast wave parameters can be described as for stoichiometric mixtures using additional scaling for the explosion
energy according to oxygen content (cloud volume). The results of large scale experiments with fuel spray clouds containing
0.16–100 tons of fuel with mean concentration from stoichiometric () up to are reconsidered. These results confirm the proposed scaling of air blast parameters for a wide range of fuel types, cloud
volumes and fuel concentrations. Detonations of fuel rich gaseous mixtures result in a strong heat radiation. Heat radiation
energy, time and size of the fireball formed are studied as a function of fuel concentration.
Received March 10, 1995 / Accepted March 12, 1995 相似文献
77.
用两相流模型对悬浮RDX炸药粉尘爆轰波进行了数值模拟。RDX炸药颗粒在爆轰波阵面后的高温高速气流中加速并升温,颗粒表面发生熔化。参考液滴在高速气流作用下剥离的效应,假设炸药熔化部分在高速气流的作用下发生剥离,破碎成极小的颗粒,瞬时发生分解反应,释放出能量支持爆轰波传播。数值模拟了在不同粒径和浓度的悬浮RDX炸药粉尘中爆轰波的发展与传播过程,得到了爆轰波流场中气-固两相的物理量分布,并确定了爆轰波参数。在较低的RDX粉尘浓度条件下,爆轰波阵面压力的峰值曲线出现振荡。当RDX粉尘浓度在80~150 g/m3时,数值模拟得到的爆轰波阵面压力峰值曲线的振荡是规则的;当RDX粉尘浓度为70 g/m3时,爆轰波阵面压力峰值曲线出现不规则振荡。 相似文献
78.
以RDX为基的含铝炸药中铝粉粒度和氧化剂形态对加速金属能力的影响 总被引:3,自引:0,他引:3
利用激光速度干涉仪研究了含微米铝粉和纳米铝粉复合炸药加速金属平板的能力,结果表明纳米铝粉的引入能够获得更大的金属平板自由面速度,其反应时间比微米复合含铝炸药缩短35.1%。研究了氧化剂的形态对含铝炸药性能的影响,用物理化学手段获得的RDX/AP复合粒子复合粒子制作的含铝炸药加速金属平板的能力优于机械混合RDX/AP的含铝炸药,前者的反应时间也比后者短。此外,还研究了以富氧炸药取代RDX获得的含铝炸药的性能,结果表明其加速金属平板的速度比RDX/Al复合炸药提高10%。 相似文献
79.
P. Ravi 《Molecular physics》2013,111(7):647-655
Azodinitro- and dinitroethylene-bridged bitriazoles are of interest in the contest of high explosives, and were found to have true local energy minima at the B3LYP/aug-cc-pVDZ level of theory. The optimised structures, vibrational frequencies and thermodynamic quantities for bitriazoles were obtained in the ground state. Kamlet–Jacobs equations were used to evaluate the performance of bitriazoles based on the predicted density and the calculated heat of explosion. Detonation properties (D = 8.12 to 9.23 km s?1 and P = 28.0 to 39.83 GPa) of bitriazoles were found to be promising compared with those of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX, D = 8.75 km s?1 and P = 34.7 GPa) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX, D = 8.96 km s?1 and P = 35.96 GPa). The fusion of azoles particularly appears to be a promising area for investigation, since it may lead to the desirable consequences of higher heat of explosion, higher density and thus improved detonation performance. 相似文献
80.
Alberto Hernández John B. Bdzil D. Scott Stewart 《Combustion Theory and Modelling》2013,17(1):109-141
We present a parallel, two-dimensional, grid-based algorithm for solving a level-set function PDE that arises in Detonation Shock Dynamics (DSD). In the DSD limit, the detonation shock propagates at a speed that is a function of the curvature of the shock surface, subject to a set of boundary conditions applied along the boundaries of the detonating explosive. Our method solves for the full level-set function field, φ(x, y, t), that locates the detonation shock with a modified level-set function PDE that continuously renormalises the level-set function to a distance function based off of the locus of the shock surface, φ(x, y, t)=0. The boundary conditions are applied with ghost nodes that are sorted according to their connectivity to the interior explosive nodes. This allows the boundary conditions to be applied via a local, direct evaluation procedure. We give an extension of this boundary condition application method to three dimensions. Our parallel algorithm is based on a domain-decomposition model which uses the Message-Passing Interface (MPI) paradigm. The computational order of the full level-set algorithm, which is O(N 4), where N is the number of grid points along a coordinate line, makes an MPI-based algorithm an attractive alternative. This parallel model partitions the overall explosive domain into smaller sub-domains which in turn get mapped onto processors that are topologically arranged into a two-dimensional rectangular grid. A comparison of our numerical solution with an exact solution to the problem of a detonation rate stick shows that our numerical solution converges at better than first-order accuracy as measured by an L1-norm. This represents an improvement over the convergence properties of narrow-band level-set function solvers, whose convergence is limited to a floor set by the width of the narrow band. The efficiency of the narrow-band method is recovered by using our parallel model. 相似文献