杀伤战斗部破片定向飞散特性研究

研究了钢预制破片壳体在四种装药爆轰驱动下的飞散特性。求得了使破片飞行路径呈平行型的预制破片壳体的临界半径及相应的破片初始速度。     

椭圆截面战斗部破片飞散特性研究

为研究椭圆截面战斗部毁伤特性,采用数值模拟与试验相结合的方法,开展了椭圆截面战斗部破片飞散特性研究。研究结果表明：椭圆截面战斗部在短轴方向的破片速度、破片分布密度全部高于长轴方向,在长短轴之比a/b=1.8条件下,短轴方向相对长轴方向的破片速度增益可以达到15%以上,破片分布密度增益可以达到440%以上,验证了椭圆截面战斗部具有在短轴方向毁伤增强的典型特点,在椭圆截面战斗部应用时,应考虑采用椭圆截面的短轴方向作为打击目标的主要方向。     

内衬对杀伤战斗部破片飞散特性影响研究

为提高杀伤战斗部破片轴向杀伤威力,基于Shapiro公式,改进杀伤战斗部内衬曲线,设计了破片飞散角为5°和9°杀伤战斗部。使用LS-DYNA有限元软件和ALE算法,对破片飞散过程进行了数值仿真计算,进行了战斗部原理样机静爆试验,证实了内衬曲线的合理性,分析了内衬曲线形状及厚度对破片飞散特性的影响。结果表明：飞散角试验值及仿真计算值与理论设计值误差在8%之内;破片飞散角设计值越小,内衬曲线曲率越大,破片初始飞散速度越小;适当增加内衬厚度,破片初始飞散速度增大,破片飞散角减小。     

椭圆变截面侵爆战斗部破片飞散特性分析

为研究爆轰驱动作用下椭圆变截面战斗部破片分布及破片速度规律,进行了多发椭圆变截面战斗部破片飞散特性试验。通过LS-DYNA软件,采用SPH(smoothed particle hydrodynamics)方法对战斗部壳体膨胀破裂飞散过程进行数值模拟,研究了底部中心点起爆方式下的椭圆变截面战斗部径向及轴向破片飞散规律。研究结果表明径向方向破片飞散规律为短轴方向破片速度及破片分布密度均大于长轴方向,二者随径向方位角增大而增大,且随着长短轴之比增大,此现象更明显。底部截面长短轴之比为1.4的椭圆变截面战斗部,短轴-长轴破片速度差达到18.7%,在短轴方向的破片数目约为长轴方向4.55倍。轴向方向上由于不断变化的截面装填比以及长短轴之比,不同径向方位角处的轴向破片速度分布不同,随着径向方向角增大,轴向速度最大破片位置由壳体底部附近逐渐靠近壳体中部。     

破片对反辐射导弹战斗部毁伤效能仿真

分析了“哈姆”反辐射导弹目标特性及破片对其毁伤模式,建立了破片对反辐射导弹战斗部毁伤效能模型,研究了不同质量破片对反辐射导弹战斗部的穿透能力和引爆能力。仿真及试验结果表明：单枚破片质量为15g,速度在1700m/s以上,就足以对反辐射导弹战斗部达到解体性毁伤,它为未来反导弹药战斗部设计提供了重要参考。     

预制破片战斗部安全距离试验与数值仿真研究

为了分析战斗部结构、装填破片质量2种因素对预制破片战斗部安全防护距离的影响,运用连续-离散耦合计算程序构建了聚焦结构、平行结构、飞散结构战斗部及装填不同质量破片的战斗部模型,结合特定的材料方程与状态方程,对破片飞散全过程进行了数值仿真,验证了静爆数值仿真的可靠性.研究结果表明:我国现行标准对于战斗部安全距离的规定过大....     

面空导弹杀伤战斗部破片飞散特性的分析与设想

本文分析了面空导弹杀伤战斗部破片飞散特性对空中目标毁伤效应的影响,并提出了为提高毁伤概率而改进杀伤战斗部破片飞散方式的一种新的设想。     

轴向增强战斗部预制破片爆炸飞散数值模拟

针对传统杀爆战斗部在垂直打击目标时产生中心杀伤盲区的问题,提出并设计了一种轴向增强杀爆战斗部结构。通过将战斗部装药头部设计为圆弧形,在装药头部周围空间均匀填充更多的预制破片来增加轴向破片的数量并改善轴向破片的飞散方向,以此实现战斗部的轴向增强功能。基于欧拉-拉格朗日单元耦合(CEL)仿真算法,采用ABAQUS有限元仿真软件开展了该战斗部毁伤威力场的数值仿真分析。仿真结果表明,大多数预制破片的速度处于800～1 500 m/s,在合理的弹目交汇条件下,战斗部能够对目标产生有效毁伤;战斗部头部的破片能够比较均匀地分布在中心毁伤区域,随着弹目交汇时战斗部轴向初速度的提高,战斗部头部破片仍然能够保持在中心毁伤区域内均匀分布。设计的轴向增强战斗部显著增加了中心毁伤区域内的破片数量,并且保证破片能够均匀分布在中心毁伤区域内,基本解决了传统杀爆战斗部产生的中心杀伤盲区问题。本文中研究成果能够支撑新型轴向增强杀爆战斗部的设计,并为定向杀伤式防空反导战斗部的设计提供参考。     

Quantification of projection angle in fragment generator warhead

Tactical Ballistic Missile (TBM) class target neutralization by the fragment spray of a Fragment Generator Warhead (FGW) calls for quantification of fragment projection angle scatter to finalize the end game engagement logic. For conventional axi-symmetric warhead, dispersion is assumed to be normal with a standard deviation of 3⁰. However, such information is not available in case of FGW. Hence, a set of experiments are conducted to determine the dispersion of fragments. The experiments are conducted with a specific configuration of FGW in an identical arena to quantify the scatter and then verified its applicability to other configurations having a range of L/D and C/M ratios, and contoured fragmenting discs. From the experimental study, it is concluded that the scatter in projection angle follows normal distribution with a standard deviation of 0.75° at Chi-square significance level of 0.01(χ²_0.99).     

小子样条件下弹头落点CEP计算方法

针对目前武器射击试验中弹头落点子样小 ,评估其CEP难的特点 ,提出一种简明实用的计算方法 ,由仿真计算表明 ,它比GJB5 2 6A— 98的点估计较优 ,此方法可在工程上予以应用     

Numerical and experimental study on the response characteristics of warhead in the fast cook-off process

The response characteristics of the warhead under thermal stimuli conditions are important to the safety improvement. The goal of this study is to obtain data on the warhead in the fast cook-off process. In this paper, a numerical calculation method is proposed, whose reliability is supported by comparison with experimental results. Through the numerical calculation, the temperature distribution, temperature change, and ignition time are acquired. The numerical results show that the ignition time is 76 s after the warhead started to burn and that the maximum temperature of the explosive's outer surface is 238.3 C at the ignition time. The fast cook-off experiment of the warhead is implemented so as to get the flame temperature and reaction grades that are not available through numerical calculation. The experimental results show that the overpressure fails to reach the preset minimum value which is equivalent to 6 kg of TNT and that the reaction grade is deflagration. The research results have reference value for the design of the warhead and the reduction of detonation risks.     

Perspectives on additive manufacturing for warhead applications

According to different damage modes,warheads are roughly divided into three types:fragmentation warheads,shaped charge warheads,and penetrating warheads.Due to limitations in material and structural manufacturing,traditional manufacturing methods make it difficult to fully utilize the damage ability of the warhead.Additive manufacturing(AM)technology can fabricate complex structures,with classified materials composition and customized components,while achieving low cost,high accuracy,and rapid production of the parts.The maturity of AM technology has brought about a new round of revolution in the field of warheads.In this paper,we first review the principles,classifications,and characteristics of different AM technologies.The development trends of AM technologies are pointed out,including multi-material AM technology,hybrid AM technology,and smart AM technology.From our survey,PBF,DED,and EBM technologies are mainly used to manufacture warhead damage elements.FDM and DIW technologies are mainly used to manufacture warhead charges.Then,the research on the application of AM technology in three types of warhead and warhead charges was reviewed and the existing problems and progress of AM technologies in each warhead were analyzed.Finally,we sum-marized the typical applications and look forward to the application prospects of AM technology in the field of warheads.     

Experimental and numerical study of the fragmentation of expanding warhead casings by using different numerical codes and solution techniques

There has been increasing interest in numerical simulations of fragmentation of expanding warheads in 3D. Accordingly there is a pressure on developers of leading commercial codes, such as LS-DYNA, AUTODYN and IMPETUS Afea, to implement the reliable fracture models and the efficient solution techniques. The applicability of the Johnson–Cook strength and fracture model is evaluated by comparing the fracture behaviour of an expanding steel casing of a warhead with experiments. The numerical codes and different numerical solution techniques, such as Eulerian, Lagrangian, Smooth particle hydrodynamics (SPH), and the corpuscular models recently implemented in IMPETUS Afea are compared. For the same solution techniques and material models we find that the codes give similar results. The SPH technique and the corpuscular technique are superior to the Eulerian technique and the Lagrangian technique (with erosion) when it is applied to materials that have fluid like behaviour such as the explosive and the tracer. The Eulerian technique gives much larger calculation time and both the Lagrangian and Eulerian techniques seem to give less agreement with our measurements. To more correctly simulate the fracture behaviours of the expanding steel casing, we applied that ductility decreases with strain rate. The phenomena may be explained by the realization of adiabatic shear bands. An implemented node splitting algorithm in IMPETUS Afea seems very promising.     

On the continued acceleration of bomb casing fragments following casing fracture

It has been said that, once a bomb casing has fractured, “detonation gases will then stream around the fragments or bypass them, and the acceleration process stops there.” However, while apparently copious gas flow through casing fractures indicates some pressure release, it is also an indication of significant gas drive pressure, post casing fracture. This paper shows two approaches to the problem of calculating the actual loss of drive. One presents first-order analytical calculations, in cylindrical geometry, of pressure loss to the inside surface of a fractured casing. The second shows the modelling of a selected example in the CTH code. Both approaches reveal that gas escape, while occurring at its own sound-speed relative to the adjacent casing fragments, has to compete with rapid radial expansion of the casing. Together with some historic experiments now publicly available, our calculations indicate that post-fracture casing fragment acceleration is, for most systems, unlikely to be reduced significantly.     

Numerical simulation of warhead transportation

The new numerical approach for analysis of the warhead transportations is suggested.This approach allows to control the warhead operability before its experimental analysis.The approach is implemented by the adequate models for the software ANSYS.Analysis of the loads at land operations and trans-portations of the warhead by natural roads,water and aviation allows to obtain the maximal values of loads,which are used in numerical simulations of the warhead.These loads give an opportunity to analyze the operability and the fatigue strength of the cartridge warhead.The numerical simulations of the attachments of the warhead combat elements are performed on the basis of the suggested method.The data of the numerical simulations verifies the operability of the fastener system of the warhead combat elements.     

制导炸弹--一种重要的空袭兵器和应对措施

根据越南战争、海湾战争和科索沃战争的战例,阐述了制导炸弹的主要战术技术特点,认为制导炸弹是未来空袭作战重要兵器,是中低空中近程地(舰)空导弹的重要目标,拦截制导炸弹是地(舰)空导弹应该着力研究的问题.论证了中低空中近程地(舰)空导弹拦截制导炸弹的可行性,并提出了应开展的专项技术研究课题.     

纵火战斗部爆炸分散仿真研究

在试验的基础上,从炸药对纵火炬的驱动和纵火炬在空中飞散两个方面,对其在战斗部静爆和动态飞行时的爆炸分散进行了仿真研究,研究结果对纵火弹的具体设计具有重要的参考价值。