Defence Technology(防务技术)最新文献_第3页

A data and physical model dual-driven based trajectory estimator for long-term navigation 基于数据和物理模型双驱动的长期导航轨迹估计器

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.006

Long-term navigation ability based on consumer-level wearable inertial sensors plays an essential role towards various emerging fields, for instance, smart healthcare, emergency rescue, soldier positioning et al. The performance of existing long-term navigation algorithm is limited by the cumulative error of inertial sensors, disturbed local magnetic field, and complex motion modes of the pedestrian. This paper develops a robust data and physical model dual-driven based trajectory estimation (DPDD-TE) framework, which can be applied for long-term navigation tasks. A Bi-directional Long Short-Term Memory (Bi-LSTM) based quasi-static magnetic field (QSMF) detection algorithm is developed for extracting useful magnetic observation for heading calibration, and another Bi-LSTM is adopted for walking speed estimation by considering hybrid human motion information under a specific time period. In addition, a data and physical model dual-driven based multi-source fusion model is proposed to integrate basic INS mechanization and multi-level constraint and observations for maintaining accuracy under long-term navigation tasks, and enhanced by the magnetic and trajectory features assisted loop detection algorithm. Real-world experiments indicate that the proposed DPDD-TE outperforms than existing algorithms, and final estimated heading and positioning accuracy indexes reaches 5° and less than 2 m under the time period of 30 min, respectively.

基于消费级可穿戴惯性传感器的长期导航能力在智能医疗、紧急救援、士兵定位等多个新兴领域发挥着至关重要的作用。现有长期导航算法的性能受到惯性传感器累积误差、本地磁场干扰和行人复杂运动模式的限制。本文开发了一种基于数据和物理模型双驱动的稳健轨迹估计（DPDD-TE）框架，可用于长期导航任务。本文开发了一种基于双向长短期记忆（Bi-LSTM）的准静态磁场（QSMF）检测算法，用于提取有用的磁场观测信息以进行航向校准；还采用了另一种 Bi-LSTM 算法，通过考虑特定时间段内的混合人体运动信息来估计步行速度。此外，还提出了基于数据和物理模型双驱动的多源融合模型，以整合基本的 INS 机械化和多层次约束与观测，从而在长期导航任务中保持精度，并通过磁场和轨迹特征辅助环路检测算法进行增强。实际实验表明，所提出的 DPDD-TE 优于现有算法，在 30 分钟的时间内，最终估计的航向和定位精度指标分别达到 5°和小于 2 米。

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引用次数: 0

A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion 基于时空序列有限多层片段分散的云模型目标损伤效果评估算法

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.008

To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept, this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory. Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion, we divide into a finite number of fragments distribution planes based on the time series in space, set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target. Building on the precondition that the multilayer fragments of the time series effectively assail the target, we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model. Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable, we introduce cloud model theory to research the target damage assessment method. Combining the equivalent simulation experiment, the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis.

为解决防空拦截中不确定弹丸与目标交点下碎片攻击目标时的目标毁伤评估问题，本文提出了一种利用时空有限多层碎片分布计算目标毁伤概率的方法和基于云模型理论的目标毁伤评估算法。借鉴弹丸近炸破片的空间弥散特性，基于空间时间序列划分有限个破片分布平面，建立基于时间序列的破片层弥散模型和交集判据，确定各层破片对目标的有效穿透力。在时间序列的多层碎片有效攻击目标的前提下，我们还建立了穿孔和穿透损伤的损伤判据，并推导出损伤概率计算模型。以时空序列中碎片层对目标的损伤概率为输入状态变量，引入云模型理论研究目标损伤评估方法。结合等效模拟实验，通过定量计算和对比分析，验证了所提方法的科学性和合理性。

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引用次数: 0

Influences of oscillation on the physical stability and explosion characteristics of solid‒liquid mixed fuel 振荡对固液混合燃料物理稳定性和爆炸特性的影响

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.014

Chi Zhang , Ge Song , Hui Guo , Jiafan Ren , Chunhua Bai

The stratification phenomenon resulting from differences in the physical properties of solid‒liquid components seriously affect the final combustion and explosion characteristics of mixed fuel under the action of oscillation. The effects of oscillation on the physical stability of mixed fuel with two solid‒liquid ratios and three liquid component distribution ratios have been investigated using a self-designed experimental system at oscillation frequencies of 60–300 r/min. The explosion characteristics of mixed fuel before and after oscillation are gained from a 20 L spherical explosion container system. When the mass ratio of liquid components is controlled at 66.9%, 64.7%, 62.6% the final explosion characteristics are stable, with a maximum difference of only 0.71%. The volume of liquid fuel precipitation increases with increasing oscillation frequency when the mass ratio of liquid components reaches 71.7%, 69.6%, 67.7%. The fuel explosion overpressure after oscillation decreases with increasing liquid precipitation volume, and the repeatability is poor, with a maximum standard deviation of 82.736, which is much higher than the ratio without stratification. Properly controlling the mass ratio of liquid components of the mixed fuel can effectively combat the impact of oscillation on the physical state and maintain the stability of the final explosion characteristics.

在振荡作用下，固液组分物理性质差异导致的分层现象严重影响了混合燃料的最终燃烧和爆炸特性。利用自行设计的实验系统，在振荡频率为 60-300 r/min 的条件下，研究了振荡对两种固液比和三种液体组分分布比的混合燃料的物理稳定性的影响。从一个 20 L 的球形爆炸容器系统中获得了混合燃料在振荡前后的爆炸特性。当液体成分的质量比控制在 66.9%、64.7% 和 62.6% 时，最终爆炸特性稳定，最大差异仅为 0.71%。当液体组分质量比达到 71.7%、69.6%、67.7% 时，液体燃料析出量随振荡频率的增加而增加。振荡后的燃料爆炸超压随液体析出量的增加而减小，重复性较差，最大标准偏差为 82.736，远高于不分层的比例。适当控制混合燃料液体组分的质量比，可有效对抗振荡对物理状态的影响，保持最终爆炸特性的稳定性。

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引用次数: 0

Kinetics and mechanism of the low-energy β-α phase transition of the second kind in 2,4-dinitroanisole 2,4-二硝基苯甲醚中低能β-α第二类相变的动力学和机理

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.04.004

In this work, comprehensive studies of 2,4-dinitroanisole (2,4DNAN) were carried out using powder thermorentgenography of the internal standard. The time of the complete polymorphic transition in the solid phase β→α in 2,4DNAN under various combinations of conditions has been determined. It has been established that, regardless of the season of manufacture of the substance, when it is stored for 8–9 months, with a change in ambient temperature from minus 30 °C to plus 30 °C, a complete polymorphic transition β→α occurs. When stored in conditions below minus 5 °C, polymorphic transition does not occur. When stored in conditions above plus 30 °C in a closed container, polymorphic transition occurs within 3 weeks. The polymorphic transition is accompanied by a decrease in density by 1.3%–1.5% and an increase in melting temperature by 10–12 °C, depending on the degree of purity of the starting substance. The activation energy of the molecular rearrangement was 68–70 kJ/mol (16.5 ± 3 kcal/mol). The mechanism of polymorphic transition has been evaluated, which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the product. The average activation energy of the polymorphic transition process was 110 ± 6.2 kJ/mol (26.2 kcal/mol). In an open container, reactions proceed by a homogeneous mechanism, and in a closed container by a heterogeneous mechanism involving the gas phase.

本研究利用内标粉末热成像仪对 2,4-二硝基苯甲醚（2,4DNAN）进行了全面研究。测定了在不同条件组合下，2,4-二硝基苯甲醚固相β→α完全多态转变的时间。结果表明，无论该物质的生产季节如何，在环境温度从零下 30 °C升至零上 30 °C、贮存 8-9 个月后，都会发生完全的多态转变 β→α。在低于零下 5 °C 的条件下储存时，不会发生多态转变。如果在高于正 30 °C 的条件下储存在密闭容器中，多态转变会在 3 周内发生。多态转变伴随着密度下降 1.3%-1.5%，熔化温度升高 10-12 °C，具体取决于起始物质的纯度。分子重排的活化能为 68-70 kJ/mol（16.5 ± 3 kcal/mol）。对多晶型转变的机理进行了评估，推测其机理是基于粉末颗粒和产物表面的内部同扩散和能量转移。多态转变过程的平均活化能为 110 ± 6.2 kJ/mol（26.2 kcal/mol）。在开放容器中，反应以均相机制进行，而在封闭容器中，反应以涉及气相的异相机制进行。

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引用次数: 0

Influence of B4C and ZrB2 reinforcements on microstructural, mechanical and wear behaviour of AA 2014 aluminium matrix hybrid composites B4C 和 ZrB2 增强剂对 AA 2014 铝基混合复合材料微结构、机械和磨损性能的影响

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.009

Considering their affordability and high strength-to-weight ratio, lightweight aluminium alloys are the subject of intensive research aimed at improving their properties for use in the aerospace industry. This research effort aims to develop novel hybrid composites based on AA 2014 alloy through the use of liquid metallurgy stir casting to reinforce dual ceramic particles of Zirconium Diboride (ZrB₂) and Boron Carbide (B₄C). The weight percentage (wt%) of ZrB₂ was varied (0, 5, 10, and 15), while a constant 5 wt% of B₄C was maintained during this fabrication. The as-cast samples have been assessed using an Optical Microscope (OM) and a Scanning Electron Microscope (SEM) with Energy Dispersive Spectroscopy (EDS). The properties such as hardness, tensile strength, and wear characteristics of stir cast specimens were assessed to examine the impact of varying weight percentages of reinforcements in AA 2014 alloy. In particular, dry sliding wear behaviour was evaluated considering varied loads using a pin-on-disc tribotester. As the weight % of ZrB₂ grew and B₄C was incorporated, hybrid composites showed higher hardness, tensile strength, and wear resistance. Notably, the incorporation of a cumulative reinforcement consisting of 15 wt% ZrB₂ and 5 wt% B₄C resulted in a significant 31.86% increase in hardness and a 44.1% increase in tensile strength compared to AA 2014 alloy. In addition, it has been detected that wear resistance of hybrid composite pin (containing 20 wt% cumulative reinforcement) is higher than that of other stir cast wear test pins during the whole range of applied loads. Fractured surfaces of tensile specimens showed ductile fracture in the AA 2014 matrix and mixed mode for hybrid composites. Worn surfaces obtained employing higher applied load indicated abrasive wear with little plastic deformation for hybrid composites and dominant adhesive wear for matrix alloy. Hence, the superior mechanical and tribological performance of hybrid composites can be attributed to dual reinforcement particles being dispersed well and the effective transmission of load at this specific composition.

考虑到铝合金的经济性和高强度重量比，轻质铝合金成为深入研究的主题，旨在改善其性能，以用于航空航天工业。这项研究工作旨在开发基于 AA 2014 合金的新型混合复合材料，通过使用液态冶金搅拌铸造来增强二硼化锆（ZrB2）和碳化硼（B4C）双陶瓷颗粒。在制造过程中，ZrB2 的重量百分比（wt%）发生了变化（0、5、10 和 15），而 B4C 的重量百分比始终保持在 5%。使用光学显微镜（OM）和扫描电子显微镜（SEM）以及能量色散光谱仪（EDS）对铸件样品进行了评估。对搅拌铸造试样的硬度、拉伸强度和磨损特性等性能进行了评估，以研究 AA 2014 合金中不同重量百分比的强化剂的影响。特别是，使用针盘摩擦磨损试验机评估了不同载荷下的干滑动磨损特性。随着 ZrB2 重量百分比的增加和 B4C 的加入，混合复合材料显示出更高的硬度、抗拉强度和耐磨性。值得注意的是，与 AA 2014 合金相比，加入 15 重量百分比的 ZrB2 和 5 重量百分比的 B4C 的累积增强材料后，硬度显著提高了 31.86%，抗拉强度提高了 44.1%。此外，研究还发现，在整个施加载荷范围内，混合复合材料销钉（含有 20 wt% 的累积增强成分）的耐磨性高于其他搅拌铸造耐磨试验销钉。拉伸试样的断裂表面显示 AA 2014 基体为延展断裂，混合复合材料为混合断裂。在施加较大载荷时获得的磨损表面显示，混合复合材料的磨损几乎没有塑性变形，而基体合金的磨损则以粘着磨损为主。因此，混合复合材料优异的机械性能和摩擦学性能可归因于双增强粒子的良好分散以及在这种特定成分下载荷的有效传递。

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引用次数: 0

Adaptive optimisation of explosive reactive armour for protection against kinetic energy and shaped charge threats 自适应优化爆炸反应装甲，以抵御动能和定型装药威胁

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.007

We evaluate an adaptive optimisation methodology, Bayesian optimisation (BO), for designing a minimum weight explosive reactive armour (ERA) for protection against a surrogate medium calibre kinetic energy (KE) long rod projectile and surrogate shaped charge (SC) warhead. We perform the optimisation using a conventional BO methodology and compare it with a conventional trial-and-error approach from a human expert. A third approach, utilising a novel human-machine teaming framework for BO is also evaluated. Data for the optimisation is generated using numerical simulations that are demonstrated to provide reasonable qualitative agreement with reference experiments. The human-machine teaming methodology is shown to identify the optimum ERA design in the fewest number of evaluations, outperforming both the stand-alone human and stand-alone BO methodologies. From a design space of almost 1800 configurations the human-machine teaming approach identifies the minimum weight ERA design in 10 samples.

我们评估了一种自适应优化方法--贝叶斯优化法（BO），该方法用于设计最小重量的爆炸反应装甲（ERA），以抵御替代中口径动能（KE）长杆弹丸和替代定型装药（SC）弹头。我们采用传统的 BO 方法进行优化，并与人类专家的传统试错法进行比较。此外，我们还对第三种方法进行了评估，即利用新颖的人机协作框架进行 BO。优化数据是通过数值模拟生成的，模拟结果与参考实验的定性一致。结果表明，人机协作方法能以最少的评估次数确定最佳的 ERA 设计，其性能优于独立的人机协作方法和独立的 BO 方法。在近 1800 种配置的设计空间中，人机协同方法只需 10 个样本就能识别出最小权重的 ERA 设计。

引用次数: 0

Topological optimization of ballistic protective structures through genetic algorithms in a vulnerability-driven environment 在脆弱性驱动环境下通过遗传算法优化弹道防护结构的拓扑结构

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.011

Reducing the vulnerability of a platform, i.e., the risk of being affected by hostile objects, is of paramount importance in the design process of vehicles, especially aircraft. A simple and effective way to decrease vulnerability is to introduce protective structures to intercept and possibly stop threats. However, this type of solution can lead to a significant increase in weight, affecting the performance of the aircraft. For this reason, it is crucial to study possible solutions that allow reducing the vulnerability of the aircraft while containing the increase in structural weight. One possible strategy is to optimize the topology of protective solutions to find the optimal balance between vulnerability and the weight of the added structures. Among the many optimization techniques available in the literature for this purpose, multi-objective genetic algorithms stand out as promising tools. In this context, this work proposes the use of a in-house software for vulnerability calculation to guide the process of topology optimization through multi-objective genetic algorithms, aiming to simultaneously minimize the weight of protective structures and vulnerability. In addition to the use of the in-house software, which itself represents a novelty in the field of topology optimization of structures, the method incorporates a custom mutation function within the genetic algorithm, specifically developed using a graph-based approach to ensure the continuity of the generated structures. The tool developed for this work is capable of generating protections with optimized layouts considering two different types of impacting objects, namely bullets and fragments from detonating objects. The software outputs a set of non-dominated solutions describing different topologies that the user can choose from.

降低平台的易损性，即受敌对物体影响的风险，在飞行器，尤其是飞机的设计过程中至关重要。降低易受攻击性的一个简单而有效的方法是采用防护结构来拦截和阻止威胁。然而，这种解决方案会导致重量大幅增加，影响飞机的性能。因此，研究既能降低飞机易受攻击程度，又能控制结构重量增加的可行解决方案至关重要。一种可行的策略是优化保护方案的拓扑结构，以在易损性和新增结构重量之间找到最佳平衡点。为此，文献中提供了许多优化技术，其中多目标遗传算法是很有前途的工具。在这种情况下，这项工作建议使用内部的脆弱性计算软件，通过多目标遗传算法指导拓扑优化过程，目的是同时最大限度地减少保护结构的重量和脆弱性。除了使用内部软件（这本身就是结构拓扑优化领域的一项创新）外，该方法还在遗传算法中加入了一个定制的突变函数，该函数专门采用基于图形的方法开发，以确保生成结构的连续性。考虑到两种不同类型的撞击物体，即子弹和引爆物体产生的碎片，为这项工作开发的工具能够生成具有优化布局的保护装置。该软件可输出一组描述不同拓扑结构的非主要解决方案，供用户选择。

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引用次数: 0

Design and evaluation of a kind of polymer-bonded explosives with improved mechanical sensitivity and thermal properties 设计和评估一种具有更好机械灵敏度和热性能的聚合物粘合炸药

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.04.005

The emergence of TKX-50, an energetic ionic salt with a high enthalpy of formation and low sensitivity, has opened a new path for the development of high-energetic, insensitive composite explosives. However, due to the poor interfacial binding properties of TKX-50 with conventional binders, there is a lack of effective guidance for the design of TKX-50 based composite explosives. To address the above issues, the interactions between carboxymethyl cellulose acetate butyrate (CMCAB) and other binders with explosives TKX-50/HMX were compared using the molecular dynamics method. Based on the simulations, TKX-50/HMX/CMCAB-based polymer-bonded explosives (PBXs) were prepared with CMCAB as binder, which displays a high binding energy (E_bind) with TKX-50 and high cohesive energy density (CED), and the effect of TKX-50 content on the performance of PBXs was investigated. The physical properties of PBXs, specifically the morphology, mechanical sensitivity, and thermal conductivity, were analyzed by SEM, sensitivity apparatus, and thermal conductivity meter, respectively. The specific heat capacity (C_p) and non-isothermal decomposition temperature of PBXs were tested by DSC, and then the corresponding thermal kinetic parameters were analyzed to evaluate their thermal safety. The adiabatic thermal decomposition processes of PBXs were tested using an ARC instrument. The decomposition mechanism and kinetics were also explored to further analyze their thermal stability and thermal safety under adiabatic conditions. The computer code EXPLO5 was used to predict the detonation parameters of PBXs. The results showed that CMCAB and TKX-50 displayed favorable interfacial bonding properties, and TKX-50 can be bonded with HMX to form a molding powder with a desirable morphology and safety profile. The TKX-50 in PBXs effectively improves the mechanical sensitivity and thermal safety of PBX and has a significant effect on the detonation performance of PBX. This research demonstrates a novel method suitable for screening and investigating high-energetic insensitive explosive systems compatible with TKX-50.

TKX-50 是一种高能离子盐，具有高形成焓和低敏感性，它的出现为开发高能、不敏感的复合炸药开辟了一条新路。然而，由于 TKX-50 与传统粘合剂的界面结合性能较差，因此在设计基于 TKX-50 的复合炸药时缺乏有效的指导。针对上述问题，使用分子动力学方法比较了羧甲基纤维素醋酸丁酸酯（CMCAB）和其他粘合剂与炸药 TKX-50/HMX 之间的相互作用。在模拟的基础上，制备了基于 TKX-50/HMX/CMCAB 的聚合物结合炸药（PBXs），以 CMCAB 为粘合剂，其与 TKX-50 的结合能（Ebind）较高，内聚能密度（CED）也较高，研究了 TKX-50 含量对 PBXs 性能的影响。分别用扫描电镜、灵敏度仪和导热仪分析了 PBX 的物理性质，特别是形态、机械灵敏度和热导率。通过 DSC 测试了 PBX 的比热容（Cp）和非等温分解温度，然后分析了相应的热动力学参数，以评估其热安全性。使用 ARC 仪器测试了 PBX 的绝热热分解过程。还探讨了分解机理和动力学，以进一步分析它们在绝热条件下的热稳定性和热安全性。利用计算机代码 EXPLO5 预测了 PBX 的爆炸参数。结果表明，CMCAB 和 TKX-50 显示出良好的界面结合性能，TKX-50 可与 HMX 结合形成具有理想形态和安全性能的成型粉末。PBX 中的 TKX-50 能有效提高 PBX 的机械敏感性和热安全性，并对 PBX 的引爆性能有显著影响。这项研究展示了一种适用于筛选和研究与 TKX-50 兼容的高能不敏感炸药系统的新方法。

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引用次数: 0

Resistance of full-scale beams against close-in explosions. Numerical modeling and field tests 全尺寸梁抵抗近距离爆炸的能力：数值建模和现场试验

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.002

This paper explores the performances of a finite element simulation including four concrete models applied to a full-scale reinforced concrete beam subjected to blast loading. Field test data has been used to compare model results for each case. The numerical modelling has been, carried out using the suitable code LS-DYNA. This code integrates blast load routine (CONWEP) for the explosive description and four different material models for the concrete including: Karagozian & Case Concrete, Winfrith, Continuous Surface Cap Model and Riedel–Hiermaier–Thoma models, with concrete meshing based on 10, 15, and 20 mm. Six full-scale beams were tested: four of them used for the initial calibration of the numerical model and two more tests at lower scaled distances. For calibration, field data obtained employing pressure and accelerometers transducers were compared with the results derived from the numerical simulation. Damage surfaces and the shape of rupture in the beams have been used as references for comparison. Influence of the meshing on accelerations has been put in evidence and for some models the shape and size of the damage in the beams produced maximum differences around 15%. In all cases, the variations between material and mesh models are shown and discussed.

本文探讨了有限元模拟的性能，包括应用于承受爆炸荷载的全尺寸钢筋混凝土梁的四种混凝土模型。现场测试数据用于比较每种情况下的模型结果。数值建模采用了合适的 LS-DYNA 代码。该代码集成了用于爆炸描述的爆炸荷载例程（CONWEP）和四种不同的混凝土材料模型，包括Karagozian & Case Concrete、Winfrith、Continuous Surface Cap Model 和 Riedel-Hiermaier-Thoma 模型，混凝土网格划分为 10、15 和 20 毫米。对六根全尺寸梁进行了测试：其中四根用于数值模型的初始校准，另外两根用于较小比例距离的测试。校准时，采用压力和加速度传感器获得的现场数据与数值模拟得出的结果进行了比较。梁的损伤面和断裂形状被用作比较的参考。网格划分对加速度的影响已得到证实，对某些模型而言，梁中损伤的形状和大小产生的最大差异约为 15%。在所有情况下，材料和网格模型之间的差异都得到了显示和讨论。

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引用次数: 0

Failure pattern in ceramic metallic target under ballistic impact 弹道冲击下陶瓷金属靶的失效模式

IF 5 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2024-10-01 DOI: 10.1016/j.dt.2024.05.012

The ballistic resistance and failure pattern of a bi-layer alumina 99.5% - aluminium alloy 1100-H12 target against steel 4340 ogival nosed projectile has been explored in the present experimental cum numerical study. In the experimental investigation, damage induced in the ceramic layer has been quantified in terms of number of cracks developed and failure zone dimensions. The resultant damage in the backing layer has been studied with variation in the bulge and perforation hole in the backing layer with the varying incidence velocity. The discussion of the experimental results has been further followed by three dimensional finite element computations using ABAQUS/Explicit finite code to investigate the behaviour of different types of bi-layer targets under multi-hit projectile impact. The JH-2 constitutive model has been used to reproduce the behaviour of alumina 99.5% and JC constitutive model has been used for steel 4340 and aluminium alloy 1100-H12. The total energy dissipation has been noted to be of lesser magnitude in case of sub-sequential impact in comparison to simultaneous impact of two projectiles. The distance between the impact points of two projectiles also effected the ballistic resistance of bi-layer target. The ballistic resistance of single tile ceramic front layer and four tile ceramic of equivalent area found to be dependent upon the boundary conditions provided to the target.

本实验和数值研究探讨了双层氧化铝 99.5% - 铝合金 1100-H12 靶件对钢质 4340 口鼻弹丸的抗弹性和破坏模式。在实验研究中，根据裂纹数量和失效区尺寸对陶瓷层的损伤进行了量化。随着入射速度的变化，背层的隆起和穿孔也随之变化，从而对背层的损伤进行了研究。在对实验结果进行讨论后，还使用 ABAQUS/Explicit 有限代码进行了三维有限元计算，以研究不同类型的双层目标在多弹头冲击下的行为。JH-2 构成模型用于重现氧化铝 99.5% 的行为，JC 构成模型用于重现钢 4340 和铝合金 1100-H12 的行为。与两个弹丸的同时撞击相比，次顺序撞击的总能量耗散较小。两枚弹丸撞击点之间的距离也会影响双层目标的抗弹性。单砖陶瓷前层和等面积四砖陶瓷的抗弹性取决于为目标提供的边界条件。

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引用次数: 0