爆轰场强对杆条姿态影响的数值模拟及试验

在圆柱形装药爆轰场强沿轴向分布的基础上,建立了实现沿离散杆长度方向上等爆轰场强加载结构的设计模型.对沿轴向爆轰场强的分布进行了数值计算,并通过试验对数学模型进行了验证.结果表明,在沿离散杆长度方向上加载爆轰场强基本相等.采用等爆轰场强控制的离散杆战斗部,杆条并未发生弯曲,而且旋转和飞散姿态一致性较好,可实现对目标的准连...     

不同起爆方式对TNT水中爆炸作用的影响

通过小型爆炸水池实验,研究了端面点起爆和中心点起爆状态下TNT装药水中爆炸能量输出结构的变化规律,并将两者进行了对比.结果表明,装药端面点起爆后,能量输出结构-冲击波压力峰值和比冲量有较大的变化,靠近起爆端方向的冲击波压力峰值和比冲量变化均较其他方位提高,端面点起爆状态比中心点起爆特定方位的冲击波压力峰值和比冲量增大约10%.得出在装药形状基本不变的条件下,改变起爆方式即可实现在水下特定方位处的爆炸能量输出结构变化.另外,聚能结构的存在,对爆炸远区冲击波比冲量的提高有益.     

炸药驱动预制破片轴向抛掷速度规律研究

为解决爆轰产物对轴向预制破片的作用压力从柱状装药中心沿径向逐渐降低,从而导致轴向预制破片抛掷速度沿径向逐渐变小的问题,研究了柱状装药长径比与装药壳体厚度等装药结构参数对轴向预制破片抛掷速度沿径向分布规律的影响,针对某种轴向前置预制破片战斗部,进行了破片轴向抛掷速度沿径向分布规律的试验.结果表明,装药长径比以及装药壳体等装药结构参数对轴向预制破片抛掷速度影响较大,通过装药尺寸、壳体厚度等参数匹配,可以调整轴向预制破片的抛掷速度.     

装药结构参数对轴向预制破片抛掷速度的影响

为研究柱形装药长径比与装药壳体厚度等结构参数对轴向预制破片抛掷速度的影响规律,以Gurney公式的假设为基础,提出爆轰产物二维运动假设条件,推导并得到轴向预制破片抛掷速度与装药长径比和装药壳体厚度之间的关系式.模拟了柱形带壳装药结构对轴向驱动预制破片抛掷速度的影响,所得结果与文献值吻合.用数值模拟结果修正关系式,得到柱形带壳装药结构参数对轴向预制破片抛掷速度的影响规律,以及轴向预制破片抛掷速度沿径向的分布规律.     

破片轴向飞散战斗部破片速度的分布规律

用数值模拟和试验两种方法研究了不同装药长径比的破片轴向飞散战斗部在单点起爆与平面起爆两种起爆方式下的速度分布特征.结果表明,装药端面中心位置处破片速度最高,沿径向大致呈抛物线趋势衰减;随着长径比的增大,破片速度增大,但增大幅度趋缓;相对于中心单点起爆,平面起爆提高了装药爆轰的瞬时度,减弱了爆轰产物气体侧向稀疏作用,能够有效提高破片速度,且速度增益在中心位置处最大,沿径向增益趋缓;就装药结构来说,长径比越大,速度增益越小,平面起爆能够更有效地提高小长径比战斗部的破片速度增益.     

复合装药偏心起爆的爆轰波特性

为研究复合装药在偏心起爆条件下的爆轰波特性,采用转镜式高速相机狭缝扫描技术对装药表面的爆轰波形传播过程进行测量,得到爆轰波在狭缝位置的扫描曲线、时空坐标以及爆轰波阵面分布图.分析了复合装药爆轰会聚波的速度分布、形成机理及传播规律,提出偏心起爆条件下复合装药爆轰波阵面前沿为凹面会聚波,会聚波可以提高内层装药爆轰波的传播速度.     

含废弃丁羟推进剂的凝胶炸药

为安全处理和再利用废弃固体推进剂,通过添加单基药将丁羟推进剂再利用制备了灌注式凝胶炸药.采用验证板试验及电离探针法研究了不同装药配比、推进剂颗粒尺寸及装药直径对炸药爆轰性能的影响.结果表明,丁羟推进剂难以发生爆轰,若添加适量单基药,能显著提高炸药的爆轰感度,并降低其临界直径;该凝胶炸药密度为1.6 g/cm3,直径为7...     

带隔板复合装药结构对双层罩毁伤元成型的影响

针对带隔板复合装药爆轰波控制问题,利用LS-DYNA软件仿真研究了不同隔板参数及复合装药结构参数对爆轰波传播及作用过程的影响;结合X光成像试验验证并通过仿真研究了双层药型罩在不同装药结构参数下的成型规律。结果表明,随着隔板厚度及复合装药高度的增加,复合装药爆轰波由球面波向V形波转化,使得双层药型罩从包覆式侵彻体向杆式侵彻体转换;其中侵彻体的头部速度和长径比与隔板厚度、装药高度、炸药性能呈正相关,与隔板半径、隔板底部距起爆中心位置、内外层炸药直径比呈负相关,当隔板厚度为0.114～0.142倍装药口径、隔板半径为0.400～0.429倍装药口径、隔板底部距起爆中心位置为0.100～0.129倍装药口径、复合装药高度为0.971～1.257倍装药口径、内外层炸药直径比为0.77～0.83时,杆式侵彻体成型较好。     

含金属-氟聚物包覆层装药的内爆性能试验研究

为研究金属-氟聚物包覆下装药在密闭空间内的爆炸释能特性,制备了金属-氟聚物与装药质量比(η)分别为0、0.30、0.63的3种试样,并在爆炸罐中开展了静爆试验,对比了3种试样爆炸后的冲击波超压、比冲量、温度与准静态压力。结果表明,金属-氟聚物包覆层显著降低了装药爆炸后的冲击波超压峰值及比冲量,但其下降规律与含惰性包覆层的装药类似,说明金属-氟聚物包覆层的二次反应对冲击波超压及比冲量没有明显贡献;而包覆层能有效提高装药爆炸后罐内的气体温度和准静态压力,当金属-氟聚物与装药的质量比为0.30和0.63时,爆炸后罐体内气体的最高温升幅度达到291K和422K,相比裸装药的254K分别提升14%和66%,而准静态压力峰值分别为0.105MPa和0.131MPa,相比裸装药的0.095MPa分别提升了10%和38%,表明η为0.63时,更能促进装药反应程度的增加。     

挠性炸药比冲量的数值模拟与实验研究

对不同厚度挠性炸药加载不同基底材料接触爆炸产生的冲量加载进行了一维数值模拟计算.采用自行研制的直线运动式冲量探头对一种0.4mm厚度的挠性炸药接触爆炸产生的冲量载荷进行了测量,得出该厚度炸药的比冲量为1234 Pa·s,数值模拟结果与实验结果符合较好.计算结果表明,挠性炸药的加载冲量与其厚度成比例增加关系;相同厚度的挠...     

Improved Momentum Method

The momentum distribution is modified by using momentum gages of rectangular cross section and of a smaller width to achieve higher angle resolution. The measurement of the impulse density distribution in the elevation direction of a cylindrical high explosive charge with a length to diameter ratio of 1.35 is up to now not presented with higher angular resolution. The impulse densities are changing more than 10 times from the bridge wave to the radial and to the forward axial direction.     

Effect of Aluminum Fiber Content on the Underwater Explosion Performance of RDX‐based Explosives

In order to analyze the effect of aluminum fiber contents on the underwater explosion performance of RDX‐based explosives, the pressure‐time curves of composite explosives with different aluminum fiber contents are measured by underwater explosion experiments. Peak pressure, impulse, shock energy, and bubble energy were obtained by analyzing the curves. The results show that the peak pressures of composite explosives decrease with increasing aluminum fiber contents. The shock impulse of the 30 % aluminum fiber composite explosive is the highest in all composite explosives. The effects of the 20 % and 40 % composite explosives are nearly equal to that of the 30 % explosive, and the different values of shock impulse among them do not exceed 5 %. The specific shock energy of the 20 % aluminum fiber composite explosive is the highest in all composite explosives. The bubble energy and explosion energy of composite explosives increase with increasing aluminum fiber contents.     

Granular flow in a rotating drum with gaps in the side wall

This paper presents a numerical investigation of the motion of bi-sized particles in a short rotating drum by using Discrete Element Method (DEM). The side wall of the drum has equally spaced gaps whose width is just between the two particle diameters. One end wall of the drum is fixed while the other rotates with the side wall. Small particles are fed into the drum continuously at the center region in the axial direction. The effect of rotating speed on the volumetric holdup and residence time of small particle is investigated. A critical rotating speed is found, below which the decrease of rotating speed will increase the volumetric holdup and the residence time of the small particles sharply. A jump in the axial distribution of the outflow rate of the small particles is observed at the region adjacent to the fixed end wall. The flow pattern inside the drum is analyzed. In the region between the fixed end wall and the feeding point, all small particles, on average, move towards the fixed end wall. While in the region between the rotating end wall and the feeding point, the small particles curve away the rotating end wall in the upper part of the charge and return to this wall in the lower part. The particle temperature distributions at different rotating speeds are explored to understand the flow behavior observed in these simulations.     

薄环形装药起爆技术研究

设计和压制了一种薄型起爆药片及环形药柱,并对其隔爆和起爆能力、可靠性和同步性进行了测试研究。采用环形装药起爆可以有效地提高聚能装药的威力,而且其威力随着环形装药直径的增加而增加。研究结果对于传爆序列的可靠性和起爆技术的研究有重要的参考价值,可用于聚能装药的起爆,提高其作战能力。     

Radial breathing mode of carbon nanotubes subjected to axial pressure

In this paper, a theoretical analysis of the radial breathing mode (RBM) of carbon nanotubes (CNTs) subjected to axial pressure is presented based on an elastic continuum model. Single-walled carbon nanotubes (SWCNTs) are described as an individual elastic shell and double-walled carbon nanotubes (DWCNTs) are considered to be two shells coupled through the van der Waals force. The effects of axial pressure, wave numbers and nanotube diameter on the RBM frequency are investigated in detail. The validity of these theoretical results is confirmed through the comparison of the experiment, calculation and simulation. Our results show that the RBM frequency is linearly dependent on the axial pressure and is affected by the wave numbers. We concluded that RBM frequency can be used to characterize the axial pressure acting on both ends of a CNT.     

壳体约束强度对温压炸药空中爆炸性能的影响

为评估壳体约束强度对温压炸药爆炸性能的影响,对不同壳体约束强度下的固体温压炸药进行野外静爆试验,用AUTODYN软件对该过程进行数值模拟,并与试验结果进行对比。结果表明,相同装药条件下,裸装药爆炸冲击波参数值、冲击波衰减速率和后燃峰压力值大于带壳装药;铝壳体装药爆炸冲击波参数值、冲击波衰减速率和后燃峰压力值较钢壳体装药高;数值模拟得到的冲击波曲线形态、峰值及冲量与试验结果吻合较好,且裸装药爆炸冲击波的后燃峰到达时间较带壳装药早,铝壳体装药爆炸冲击波的后燃峰到达时间较钢壳体早;初始冲击波超压值受壳厚影响较大,壳体的存在使冲击波的传播滞后。