Q235钢板对平头弹抗侵彻特性研究

为分析靶体结构对其抗侵彻特性的影响,利用轻气炮进行平头杆弹正撞击单层板和等厚接触式三层板的实验,获取相关的撞击过程图片.通过撞击实验,得到这两种结构靶体的初始-剩余速度曲线以及弹道极限,撞击速度为190~450 m/s.研究靶体结构对抗侵彻特性的影响,包括靶板的失效模式和抗侵彻性能.最后,采用ABAQUS/EXPLICIT软件对杆弹撞击金属板的过程进行数值模拟研究,通过对比数值模拟和实验结果,验证了数值模拟材料模型和参数的有效性.结果表明:多层板的弹道极限高于等厚单层板,并且多层板和单层板的主要失效模式之间存在差异.对于多层板,靶板失效模式与其在靶中位置相关.     

陶瓷/船用钢抗破片模拟弹侵彻的实验研究

为了获得破片模拟弹对陶瓷/船用钢靶板的侵彻规律,实验研究了10 g破片模拟弹侵彻不同厚度配比的陶瓷/船用钢靶板的弹道极限,分别分析了陶瓷面板和船用钢背板的变形情况及弹道极限随陶瓷厚度和船用钢厚度的变化关系.陶瓷面板呈现完全贯穿横向的径向裂纹和向靶前喷射的陶瓷碎粒,破口直径远大于弹体直径;船用钢背板在弹道极限附近呈现出隆...     

铝双层板结构高速撞击防护性能实验

采用非火药驱动二级轻气炮发射球形铝质弹丸,对铝双层板结构进行高速撞击实验研究,从而模拟空间碎片对航天器防护结构的高速撞击作用.实验得到了该铝双层板结构的前后板在不同速度区间的高速撞击损伤模式.获得了弹丸撞击速度在0.5~5.0 km/s时该铝双层板结构的撞击极限曲线,并与Christiansen方程的预测撞击极限曲线进行比较,同时分析了后板材料的屈服强度对铝双层板结构高速撞击防护性能的影响.     

大范围着速下混凝土靶抗冲击试验研究综述

为了评估混凝土材料的抗冲击侵彻性能,基于既有的试验结果在4个冲击速度区间内围绕混凝土靶的破坏特点及若干要素对靶体行为的影响规律展开论述.总结2种主要的速度分区思路,建议综合考虑材料动力学响应特征和表观侵彻现象的4个速度区间,按照从低速到超高速的顺序展开论述:在低速区间内(撞击速度不超过40m/s)简要介绍梁、柱、板壳的破坏模式,中速区间内(撞击速度为40~1 000m/s)论述弹靶相对尺寸、粗骨料、单轴抗压强度和钢筋对混凝土厚靶侵彻效应的影响,高速区间内(撞击速度为1.0~2.0km/s)描述半流体转变速度和成坑效应,超高速区间内(撞击速度超过2km/s)描述密度效应占主导的流体侵彻行为.对未来混凝土材料侵彻效应的研究提出若干建议.     

加筋板架击穿概率分析

为评估攻击武器作用下舰船结构的安全性,对战斗部冲击载荷作用下加筋板架的击穿概率进行分析.取初始撞击速度、战斗部密度、材料的弹性模量和极限强度作为随机变量,利用随机数生成程序得到50组随机变量的初始值;采用有限元程序进行仿真计算,得到战斗部击穿板架后的末速度值,并检验末速度是否服从正态分布,若不服从则利用最大熵法拟合末速度的概率密度函数;考虑战斗部撞击点和板架加强筋的相对位置关系,采用速度破坏准则,利用蒙特卡罗方法模拟得到不同入射角度的战斗部击穿单层和双层加筋板架的概率.该方法所用样本数量少,充分利用了样本信息,效率较高,具有一定实际应用价值.     

叠层靶对低速弹丸的抗侵彻性分析

层间界面位置对由薄厚两层钢板组成的叠层靶的抗侵彻性具有重要影响.本文对低速弹丸侵彻叠层靶问题进行了量纲分析和数值模拟,对层问界面位置对叠层靶抗侵彻性的影响规律进行了研究.分析认为:弹丸低速侵彻中厚靶条件下,随着叠层靶界面位置沿弹丸侵彻方向的移动,叠层靶的抗侵彻性先增大后减小,并存在一个极大值.典型试验结果表明:在给定试验条件下,上下层厚度比为2.0的叠层靶,抗侵彻性明显好于上下层厚度比为0.5的叠层靶.     

地下混凝土防护结构抗冲击可靠性分析

为研究地下混凝土防护结构在冲击作用下的可靠性.基于国内外已有理论及试验研究成果,得到圆锥形弹头弹体侵彻混凝土靶体形成的弹坑区和空腔区的深度计算公式,建立地下浅埋混凝土靶体侵彻深度的极限状态函数,利用已有的随机变量统计数据以及敏度分析结果,采用一次二阶矩法,对结构的失效概率进行了计算,并对影响结构失效概率的主要因素进行了分析.分析表明:在给定冲击作用下,钢筋混凝土板的失效概率随冲击速度的增加和板厚度的减小而线性降低,混凝土强度等级对结构可靠性影响不大.     

复合靶板抗侵彻能力数值仿真研究

为研究SiC陶瓷、玻璃纤维和RHA钢材料及厚度配比对三层复合靶板抗侵彻能力的影响,建立杆式穿甲弹侵彻三层复合靶板的数值仿真模型,通过对比弹丸侵彻靶板后的剩余速度,分析不同材料厚度配比复合靶板抗侵彻能力。研究结果表明：当RHA钢背板及复合靶板总厚度一定时,增加陶瓷的相对厚度能有效提高复合靶板的抗侵彻能力;三层厚度比例为1∶5∶4的200mm复合靶板具备良好的抗侵彻能力,同时靶板质量相对较小,可以为复合靶板的结构设计提供参考。     

压电、压磁耦合弹性介质圆板的自由振动

依据横观各向同性压电、压磁耦合弹性介质材料的动力学方程,导出了压电、压磁弹性圆板在轴对称变形下的状态变量方程,在给定的边界条件下,通过Caylay—Hamilton原理和利用传递矩阵方法,导出了单层和多层压电、压磁耦合弹性介质圆板自由振动的状态变量解．算例表明,得到了在不同情况下板的最低阶频率随板厚跨比的变化规律,得知压电、压磁材料层合板的振动特性与材料的叠层顺序有关．     

装配式ALC复合墙体隔声性能实验研究

ALC板材是一种新型轻质板材,将其用于建筑中,可以减轻结构的荷载,降低建筑造价。然而,单一轻质材料的墙体隔声性能难以达到设计要求。进行了内填岩棉层的双层ALC板复合墙隔声实验,获得了在各主要频段的隔声量数据。结果表明:采用此种构造的复合墙,其隔声性能较相同厚度或相近面密度的ALC板墙更为优越;内填岩棉层使ALC板复合墙体在高频段的隔声性能提升明显;选取等厚的双层ALC板所得的复合墙体吻合效应仍较为明显。     

Experimental Study on Penetration and Perforation of Laminated Kevlar

The penetration behavior and perforation characteristics of Kevlar/Epoxy laminates with various thickness in quasi-static and ballistic perforation penetrated by steel projectiles with different noses are investigated. Quasi-static tests are conducted on MTS810 testing system. The results indicate that global deformation is the major mechanism of energy absorption and woven laminates exhibit larger energy dissipation than that of angleplied laminates. Therefore, the woven laminates have better quasi-static penetration resistance. Ballistic tests with velocity of 200 - 700 m/s are executed by using a powder gun with 7.62 mm barrel. Comparing ballistic experimental results with those under quasi-static condition, both the perforation performance and the failure modes are related closely to the speed of penetrator. Quite different from quasi-static tests, ballistic tests indicate that thick angle-plied laminate targets are even better than woven laminates in resisting ballistic impact. It is observed that the damage zone of the laminate is localized highly with the increasing of the impact velocity and correspondingly, the failure modes are more manifold. The shape of projectile noses affects the impact resistance of laminated Kevlar significantly in the range of velocity around the ballistic limit.     

陶瓷装甲材料抗侵彻性能的有限元分析

采用ANSYS/LS-DYNA有限元程序对钨杆弹侵彻陶瓷(YB-AD90陶瓷)厚靶和陶瓷复合靶(钢 陶瓷 钢)建立有限元模拟,并进行数值分析,采用2种弹型(平头弹和尖头弹)的穿甲弹分析了穿甲弹的侵彻深度与弹速、弹型及靶厚之间的关系.     

Penetration depth for yaw-inducing bursting layer impacted by projectile

In order to accurately estimate the anti-penetration capacity of yaw-inducing bursting layer with irregular barriers on surface impacted by projectile, the theoretical model of attack angle and angular velocity for projectile impacting on irregular barrier was achieved according to the macroscopic relation of contact force versus contact time, in which the main factors such as the relative geometrical characteristics of projectile and irregular barrier, material property and impact velocity of projectile influencing on yaw-inducing effectiveness were considered. On the basis of considering synthetically the influences of attack angle, impact velocity, impact angle of projectile and uncontrolled free surface of target, the theoretical formulation of penetration depth for bursting layer with irregular barriers on surface impacted by projectile was presented by expressing the stress of an optional point on the nose of projectile according to the relation of stress versus velocity. The theoretical results indicate that in the case of oblique impact embodying effect of attack angle, the penetration depth is reduced with the increase of impact angle, attack angle or angular velocity, and penetration trajectory is also deflected obviously. The effectiveness of angular velocity influencing on penetration depth is increased with impact velocity increasing. The theoretical results are in good agreement with test data for low impact velocity.     

Numerical simulation for deformation of multi-layer steel plates under underwater impulsive loading

To further understand the dynamic deformation and impact resistance of thin-plate hull structure under impulse wave,the deformation of multi-layer steel plates under underwater impulsive loading has be...     

用MCA研究穿甲弹长细比对侵彻能力的影响

用可移动元胞自动机数值模拟方法,对不同长细比钨合金穿甲弹芯侵彻装甲靶板进行二维数值模拟.论述了对于一定着速和质量的穿甲弹,改变其长细比,弹、靶的破坏变形过程,得到了侵彻深度与长细比的关系曲线.数值模拟结果与已有实验现象相符合.     

超空泡射弹尾部冲击载荷的仿真研究

为了研究超空泡射弹尾拍冲击载荷的特性,利用Logvinovich G.V.的独立膨胀原理对流体域提出了一种简化处理模型,并采用流固耦合的方法,对初始扰动角速度、射弹质量、质心位置和刚度对尾拍力的影响进行了仿真计算.结果表明：初始角速度和弹体质量的增加都会使尾拍力增大,而弹体弹性模量的增加会使尾拍力变小;碰撞次数随初始角...     

Study on Overall Concept Planning of Terminal Correction Mortar Projectiles

The system composition, the operational principle of terminal correction mortar projectiles (TCMP) and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuration layout for TCMP are made in this paper, and its aerodynamic coefficients are calculated by using computational fluid dynamics (CFD) software. Test results of TCMP simulated ballistic projectiles indicate the designed TCMP can satisfy the interior ballistic demand and has a fine flight stability. The drag coefficients identified from the radar velocity-time data are in accord with the CFD computed results. According to the exposure frequency of the ground laser designator, a four-quadrant impulse correction scheme and a high exposure frequency impulse correction scheme are brought. The latter can calculate the target azimuth angle by counting the times of the facula passing through one quadrant. Simulation results also show that the guidance precision of the velocity pursuit is higher than that of the body pursuit, and the detector axis is less circuitous. Researches on the typical trajectory indicate that the terminal impulse correction can improve the hit precision of TCMP remarkably.     

不同头型高速射弹垂直入水数值模拟

为研究不同射弹头型对高速射弹垂直入水的流体动力和流场特性的影响,采用有限体积法和VOF(volume of fluid)多相流模型,并引入动网格技术,对5种不同头型的轴对称高速射弹垂直入水过程进行了数值模拟,分析了头型对空泡形态演化过程、射弹流体动力及弹道特性的影响规律.研究结果表明,头型对射弹入水空泡形态、表面闭合时间以及入水阻力、深度、速度均有较大影响.球头与截球头空泡半径小于其余3种头型,表面闭合时刻依平头、球头、锥头、截锥头的顺序递增.射弹头部均承受较大压力,球头、截球头射弹头部压力分布不均使之承受较大的剪切力.射弹头部流线型越好,入水速度衰减越慢,入水深度增加越快.入水阻力系数峰值按平头、截球头、截锥头、锥头、球头的顺序递减.     

不同头型运动体高速入水空泡数值模拟

运动体头型对其入水流场的流动分布、流体动力及入水弹道均有较大的影响。针对此问题基于有限体积法离散、求解雷诺平均的Navier?Stokes方程,考虑空化效应,并引入动网格技术,对带有不同角度锥头圆柱体的高速入水问题开展数值模拟研究,得到不同头型条件下高速入水运动参数及空泡形态发展规律、流场的压力分布及速度分布规律,分析了头型对入水空泡流场的影响。研究结果表明,空泡半径的扩张规律受头型及其阻力系数的影响,半径大小与阻力系数近似满足一定的关系式;入水初期,运动体头部受到极强的冲击载荷,锥角越大,压力峰值也越高;锥体表面压力系数与锥角大小直接相关,锥角较大时压力系数也较大。同时,锥角大小对运动体肩部排开水的速度也有较大影响,运动体在相同速度下,锥角较大时,肩部排开水的速度也较大。     

Strain Measurement for Hollow Projectiles During Its Penetration of Concrete Targets

Gives a new technique to measure the dynamic deformation behavior and strain development of a hollow steel projectile during its penetration of concrete targets. Direct straint was performed by applying strain gages attached to the inner walls of the hollow projectile, linked with on-board testing and storage recorder.This on-board test-record system is easy to operate, cost-effective and can provide reasonable, accurate and detailed information. Obverse ballistic experiments were carried out on ogival-nose hollow projectiles normally impacting concrete targets at velocities from 150m/s to 300m/s. The deformation process of projectiles was measured, recorded and played back. Profiles of voltage-time relationship were successively obtained and transfered to strain-time relationship with the aid of calibration tables. It was found that projectiles go through a series of compression and tension deformations intermittently. Relationships between strain development and projectile deformation process were discussed.