约束条件及装药直径对HMX/F2641传爆药爆压影响的实验研究

采用锰铜压力传感器法测量了约束条件和装药直径对传爆药HMX/F2641爆压的影响,传爆药密度为90%的理论密度。装药直径小于5mm时,小型化传爆序列爆压随装药直径和约束条件阻抗的减小而降低,装药直径3～5mm范围内,约束条件及装药直径对传爆药爆压的影响较小;在装药直径1.5～3mm范围内,小型化传爆序列约束条件和装药直径对传爆药爆压的影响较大。在装药密度一定时,通过装药尺寸及约束条件的匹配,可以控制并调整传爆药的爆压输出来满足不同主装药起爆的需求。     

爆轰波在扩张管内临界传播特性的研究

由于稀疏波的作用，爆轰波在变截面扩张管内传播时会发生衰减。临界条件下，爆轰波恰能在扩张管内维持自持传播的特性，称为爆轰波的临界传播特性。针对Ｃ＿２Ｈ＿２－Ｏ＿２－Ａｒ不同的爆轰气体成份，在不同扩张半角的方形扩张管内，作者研究了临界初压ｐ＿（ｃｒ）、胞格尺寸Ｓ与扩张半角的关系，用Ｗｈｉｔｈａｍ理论与重点火准则分析了爆轰波在扩张管的传播，得到胞格尺寸的计算值与实验值基本相符。     

带隔板装药爆轰波马赫反射理论研究和数值模拟

基于三波理论和Whitham方法对带隔板装药爆轰波相互作用后发生的正规反射和非正规反射进行了理论分析,给出了爆轰波发生马赫反射时临界入射角和马赫杆增长角等参数的变化规律,提出了马赫杆高度的计算模型。基于凝聚炸药爆轰Jones-Wilkins-Lee(JWL)模型和冲击起爆的Lee-Tarver模型,利用有限元计算软件对带隔板装药爆轰波的传播过程进行了数值模拟。结果表明,发生马赫反射后,随着爆轰波的传播,马赫杆的高度不断增加。数值模拟结果与理论计算结果吻合较好,说明本文中采用的理论模型和数值模拟方法能够较准确地描述带隔板装药爆轰波马赫反射的传播过程。     

爆轰波拐角传播三维数值模拟

为了研究爆轰波在拐角中的传播特性以及拐角爆轰低压流场现象,用LSDYNA 3D程序对三种常见的拐角装药的爆轰波传播特性进行了数值模拟,清晰显示了爆轰波因拐角处爆轰波传播面积的变化而产生的衰减 增长过程,讨论了侧向三通中爆速的变化情况,并得到了拐角处低压爆轰区的尺寸。     

TATB微观结构对炸药爆轰波传播性能的影响

采用不同工艺方法制备出了3种具有不同微观结构特征的超细TATB炸药粉体,用2％(质量分数)的F2311作粘结剂,压制出了不同密度的TATB基炸药试样。采用飞片短脉冲冲击起爆装置,研究了TATB基炸药中爆轰波的传播性能。研究结果表明,在一定的短脉冲冲击起爆条件下,TATB微观结构对炸药爆轰波传播性能影响较为明显。     

调控燃烧室燃料初始分布建立稳定旋转爆轰波的方法

旋转爆轰发动机具有比传统航空航天发动机更高的燃烧效率,近年来引起人们的关注。其中,点火启动过程尤为重要。为达到一次点火就能在燃烧室内建立稳定旋转爆轰波的目的,本文提出通过控制点火前燃料初始分布来建立稳定旋转爆轰波的方法,并基于纳维-斯托克斯方程与10组分27可逆反应基元化学反应模型的数值模拟验证了该方法的可行性。对旋转爆轰波传播特性的研究表明,燃料在发动机燃烧室中的分布是影响旋转爆轰波建立的关键。在燃料喷注压力较低时此影响尤为明显,它决定了爆轰波发展第一周期内波前燃料层厚度。而波前燃料层与波的稳定传播密切相关。基于该方法,本文对燃烧室初始流速为360 m/s,喷注总压0.4 MPa的旋转爆轰发动机实现了点火至稳定爆轰,得到的爆轰波传播平均速度为1 604 m/s,频率为5 347.6 Hz。此外,燃料初始填充率作为燃料初始分布的量化指标,文中给出了它建立稳定旋转爆轰时的临界范围。     

孔隙度对PBX炸药冲击起爆影响的实验研究

为了研究孔隙度(装药密度)对PBX炸药冲击起爆爆轰成长的影响,采用炸药冲击起爆锰铜压阻一维拉格朗日实验测试系统,测量了不同孔隙度的PBXC03炸药(HMX的质量分数为87%,TATB的质量分数为7%,黏结剂的质量分数为6%)冲击起爆过程不同拉格朗日位置的压力-时间历史。结果显示:在本文装药范围和加载条件下,孔隙度对PBX炸药冲击起爆爆轰过程的影响不单调,中等密度的炸药冲击起爆和爆轰成长最快,这是热点点火过程与燃烧反应过程共同作用的结果。     

流动系统中爆轰波传播特性的数值模拟

基于带化学反应的二维Euler方程,采用氢气/空气的9组分19步基元反应简化模型,对充有当量 比的氢气/空气预混气体的矩形爆轰流场中爆轰波的传播过程进行了数值模拟,讨论了均匀来流对爆轰波传 播的影响。数值结果表明,在均匀来流的影响下,上游方向上的燃烧强度大于C-J爆速,下游方向上的燃烧强 度小于C-J爆速;上游方向传播的爆轰波的阵面压力大于下游方向传播的爆轰波的阵面压力。所以,经典的 C-J爆轰理论并不适用于流动系统中爆轰波传播特性的研究。     

气体非稳定爆轰波在具有声学吸收壁的直角三通弯管中传播特性研究

本文实验研究了丙烷、氧气和空气的预混气体非稳定爆轰波在具有声学吸收壁的直角三通弯管中传播特性，分析了声学吸收材料厚度对非稳定爆轰波传播特性的影响．实验结果表明，在直角三通弯管中安装声学吸收材料对气体非稳定爆轰波有明显的衰减作用，在弯管前后非稳定爆轰波的传播速度和压力都有很大程度的减小．而且随着声学吸收材料厚度的增加，气体非稳定爆轰波强度衰减幅度增大．这一实验结论对工业安全具有重要的参考价值．     

乳化炸药铁板凹槽弯曲装药的实验研究

用铁板凹槽装填乳化炸药,通过离子探针法测得不同装药截面积和不同装药曲率条件下乳化炸药 爆炸传播速度,分析弯曲装药条件下装药直径和装药曲率对爆轰波在乳化炸药中传播速度的影响。结果表 明,爆轰波传播速度随着装药直径的二次方和曲率半径的减小而线性衰减,当装药直径或曲率半径小到某一 临界值时其爆轰反应中止。通过大量实验数据计算得到乳化炸药特定曲率半径和装药直径条件下的爆轰波 传播速度计算的经验公式。     

CL-20/HMX共晶冲击起爆模拟

采用非平衡分子动力学方法模拟了CL-20/HMX共晶炸药冲击压缩和化学反应行为,获得了密度以及粒子速度的时空分布、冲击雨贡纽、冲击起爆压力、爆轰压力等数据,以及主要中间产物和稳定产物分布。模拟结果显示,共晶的初始分解路径是CL-20中N—NO₂键断裂,主要稳定产物是N₂、CO₂和H₂O。CL-20和HMX的分解速率随着冲击波速度的增加而增加,并且逐渐接近,但各冲击条件下CL-20分子的衰减速率均大于HMX。     

锥形长药柱水下爆炸冲击波参数计算方法

为了计算锥形长药柱水下爆炸冲击波压力,以及研究长脉宽冲击波的传输特性,基于叠加原理建立了冲击波压力-时间曲线的计算方法,通过实验验证了该方法的有效性,在此基础上分析了锥形长药柱不同方位冲击波压力的分布规律。研究结果表明:锥形长药柱产生的冲击波压力具有各向异性,在起爆端一侧形成的是具有厚波头特征的低幅值长脉宽冲击波,在装药径向形成的是接近指数衰减的高幅值冲击波,而在远离起爆端的冲击波压力幅值和脉宽则介于前两者之间。锥形长药柱与球形装药冲击波分布的差异是由于装药形状和起爆方式的改变所导致的,由于装药不同部位起爆的时间差,导致水下爆炸冲击波在不同位置的叠加效果存在明显差异,药柱周围流场中形成的冲击波压力具有方向性。利用提出的计算方法得到的计算结果与实验结果和数值模拟结果吻合较好,研究结果可为锥形长药柱水下爆炸冲击波威力场和毁伤评估提供参考和依据。     

Explosive dispersal of solid particles

Abstract. The rapid dispersal of inert solid particles due to the detonation of a heterogeneous explosive, consisting of a packed bed of steel beads saturated with a liquid explosive, has been investigated experimentally and numerically. Detonation of the spherical charge generates a blast wave followed by a complex supersonic gas-solid flow in which, in some cases, the beads catch up to and penetrate the leading shock front. The interplay between the particle dynamics and the blast wave propagation was investigated experimentally as a function of the particle size (100–925 m) and charge diameter (8.9–21.2 cm) with flash X-ray radiography and blast wave instrumentation. The flow topology during the dispersal process ranges from a dense granular flow to a dilute gas-solid flow. Difficulties in the modeling of the high-speed gas-solid flow are discussed, and a heuristic model for the equation of state for the solid flow is developed. This model is incorporated into the Eulerian two-phase fluid model of Baer and Nunziato (1986) and simulations are carried out. The results of this investigation indicate that the crossing of the particles through the shock front strongly depends on the charge geometry, the charge size and the material density of the particles. Moreover, there exists a particle size limit below which the particles cannot penetrate the shock for the range of charge sizes considered. Above this limit, the distance required for the particles to overtake the shock is not very sensitive to the particle size but remains sensitive to the particle material density. Overall, excellent agreement was observed between the experimental and computational results. Received 16 August 1999 / Accepted 26 June 2000     

Three-dimensional cellular structure of detonations in suspensions of aluminium particles

Recently, we have used scarce available data on the detonation cell size in suspensions of aluminium particles in air and oxygen to adjust the kinetic parameters of our two-phase model of detonations in these mixtures. The calculated detonation cell width was derived by means of two-dimensional (2D) unsteady simulations using an assumption of cylindrical symmetry of the flow in the tube. However, in reality, the detonation cells are three-dimensional (3D). In this work, we have applied the same detonation model which is based on the continuous mechanics of two-phase flows, for 3D numerical simulations of cellular detonation structures in aluminium particle suspensions in oxygen. Reasonable agreement on the detonation cell width was obtained with the aforementioned 2D results. The range of tube diameters where detonations in $\text{ Al/O}_2$ mixture at a given particle size and concentration would propagate in the spinning mode has been estimated (these results make a complement to our previous analysis of spinning detonations in Al/air mixtures). Coupling these results with the dependencies of detonation cell size on the mean particle diameter is of great interest for the understanding of fundamental mechanisms of detonation propagation in solid particle suspensions in gas and can help to better guide the experimental studies of detonations in aluminium suspensions. It is shown that the part of detonation wave energy used for transverse kinetic energy of both gas and particles is quite small, which explains why the propagation velocity of spinning and multi-headed detonations reasonably agrees with the ideal CJ values.     

斜波压缩下HMX晶体的弹塑性行为

开展了（010）、（011）晶向HMX晶体的斜波压缩实验,获得了约15 GPa压力下的速度响应剖面。实验结果表明,HMX单晶存在明显弹塑性转变行为,且速度波形有下降趋势,这是材料的黏性效应导致,材料的弹性极限随着样品厚度增加而变化,不同晶向的材料动力学特性存在差异。结合Hobenemser-Prager黏弹塑性本构关系和三阶Birch-Murnaghan物态方程开展了HMX晶体斜波压缩物理过程的数值模拟,计算结果可以很好地描述HMX晶体的弹塑性转变这一物理过程。     

PETN、RDX和HMX炸药爆轰参数的数值模拟

用吉布斯自由能最小原理,通过解化学平衡方程组,求解PETN、RDX和HMX炸药爆轰产物系统的平衡组分,计算结果与用BKW和LJD方法计算的结果相近。用自编的程序从碳的石墨相、金刚石相、类石墨液相和类金刚石液相4种相态中确定出炸药爆轰产物中游离碳更可能存在的相态,并用此相态计算碳的吉布斯自由能。以WCA状态方程作为爆轰气相产物的物态方程,对PETN、RDX和HMX炸药爆轰参数作了预言,爆轰CJ点的爆速、爆压和爆温的计算结果与实验值吻合得很好。     

Shock and detonation wave diffraction at a sudden expansion in gas–particle mixtures

Numerical modeling of the propagation of shock and detonation waves is carried out in a duct with an abrupt expansion for a heterogeneous mixture of fine particles of aluminum and oxygen. A considerable difference from corresponding flows in pure gas is found. The influence of the size and mass loading of particles on the flow and shock wave structure behind the backward-facing step is determined. As in gaseous detonations, three types of scenarios of detonation development are obtained. Specific features of the flow structure are revealed such as deformation of the combustion front due to interaction between the relaxation zone and the vortex structure. The influence of particle size and channel width on detonation propagation is analyzed. This paper is based on work that was presented at the 21th International Colloquium on the Dynamics of Explosions and Reactive Systems, Poitiers, France, July 23–27, 2007.     

几种常用炸药的爆压与爆轰反应区精密测量

为了获得几种常用炸药的爆压和反应区宽度数据,采用激光干涉测试技术对TNT、PETN、RDX、HMX、TATB和CL-20炸药的稳态爆轰波界面粒子速度进行了测试,获得了高精度的界面粒子速度时程曲线,利用阻抗匹配公式计算得到了炸药的爆压。结果表明:PETN、RDX、HMX和CL-20等理想炸药的界面粒子速度曲线存在较明显的拐点,爆轰反应区较窄,反应时间为7~15 ns。TNT和TATB炸药由于存在碳凝聚慢反应过程,界面粒子速度曲线没有明显的拐点,爆轰反应时间分别为（100±15） ns和（255±20） ns。初步的不确定度分析表明,激光干涉法测试爆压的相对扩展不确定度为4.4%（包含因子k=2）。     

圆盘结构下旋转爆震波传播特性的实验研究

为研究圆盘结构下旋转爆震波的传播特性,通过改变反应物的质量流率及当量比,在非预混圆盘形旋转爆震模型发动机（rotating denonation engine,RDE）上进行实验研究。结果表明,爆震波在圆盘形RDE上成功起始并能够连续传播,得到了两种传播模态:单波模态和双波模态,在发动机工作过程中发现,集气腔与燃烧室存在相互作用。当反应物质量流率小于159.20 g/s时,旋转爆震波以单波模态稳定传播,爆震波传播频率为4.56~4.62 kHz,越靠近燃烧室外圆,爆震波的压力峰值及传播速度越大;当质量流率大于186.89 m/s时,旋转爆震波以双波模态传播,传播频率为8.59~8.64 kHz。双波传播模态经历四个阶段:起爆阶段的单波段、稳定双波段、不稳定双波段、排气阶段转单波段。当质量流率介于159.20~186.89 g/s之间时,旋转爆震波以单/双波混合模态传播。反应物当量比在1附近时,爆震波的传播过程较稳定,偏离1,爆震波传播不稳定,初始阶段起爆失败或传播过程中存在间断。     

Critical tube diameter for detonation transmission and critical initiation energy of spherical detonation

Two experimental setups are used to study propagation and attenuation of blast waves. In the first one, the blast wave is generated by a spherical detonation, and in the second one, the blast wave is created by the diffraction of a planar detonation propagating in a tube. The similarity of these phenomena appears clearly by means of dimensionless space-time and pressure-space diagrams of shock wave propagation. Dimensionless variables are expressed as a function of the supplied energy. Two energy formulations are proposed: a piston model and a bulk energy model. The established diagrams cover a wide range of industrial applications. Under critical conditions, the energy released by a planar detonation is correlated to the ignition source energy supply and a relationship which links the critical radius of detonation to the critical tube diameter. Received 5 July 1997 / Accepted 13 July 1998