International Journal of Impact Engineering最新文献_第3页

Hypervelocity impact against aluminium Whipple shields in the shatter regime with systematic parameter variation: An experimental and numerical study 在碎裂状态下对铝制威普尔防护罩的超高速撞击与系统参数变化：实验和数值研究

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-24 DOI: 10.1016/j.ijimpeng.2024.105126

{"title":"Hypervelocity impact against aluminium Whipple shields in the shatter regime with systematic parameter variation: An experimental and numerical study","authors":"","doi":"10.1016/j.ijimpeng.2024.105126","DOIUrl":"10.1016/j.ijimpeng.2024.105126","url":null,"abstract":"<div><div>Aluminium Whipple shields are commonly used to protect spacecraft against hypervelocity impacts (HVIs) from orbital debris and micrometeoroids. Since numerical models nowadays are vital in the design process of protective shields, experimental studies of HVI are important to ensure that the numerical methods are robust and capable of accurately describing a range of impact conditions and material responses. The shatter regime is the transition velocity range between ballistic impact and hypervelocity impact, typically defined from 3 to 7 km/s. In this region, the debris cloud generated by the impact transitions from a few large, solid fragments at the lower end of the velocity range, to a high number of smaller fragments and partial melting of the projectile at the higher velocities. In this study, an experimental campaign of 22 normal impacts of spherical AA1100 projectiles on AA6061-T6 Whipple shields is performed, where the impact velocity and bumper thickness are systematically varied to study the change in debris cloud characteristics and shield damage. Impact velocities from 2.6 to 5.0 km/s are investigated, combined with bumper thicknesses of 1.0, 1.5 and 2.0 mm. Analysis of the experimental results is conducted using high-speed camera footage of the debris clouds and post-impact analysis of bumpers and rear walls. A numerical model is then established using the Smoothed Particle Hydrodynamics (SPH) method in the IMPETUS Solver, and the numerical results are compared to the experimental data. The simulations are able to capture the main trends found in the experimental study, and show a similar level of damage as the experiments when varying the impact velocity and bumper thickness. The simulations have somewhat smaller fragments generated in the debris cloud than in the experiments, leading to slightly less damage inflicted on the rear wall.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correction method and verification of radial inertia and friction effects under a unified deformation framework in SHPB experiments on soft materials 软材料 SHPB 实验中统一变形框架下径向惯性和摩擦效应的修正方法与验证

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-20 DOI: 10.1016/j.ijimpeng.2024.105129

{"title":"Correction method and verification of radial inertia and friction effects under a unified deformation framework in SHPB experiments on soft materials","authors":"","doi":"10.1016/j.ijimpeng.2024.105129","DOIUrl":"10.1016/j.ijimpeng.2024.105129","url":null,"abstract":"<div><div>During the split Hopkinson pressure bar (SHPB) experiments, significant measurement errors can arise due to severe radial inertia and friction effects. Previous studies have developed various correction methods for these two effects. However, these methods have problems such as over-reliance on the volume invariance assumption of the specimen and inconsistent assumptions on the deformation patterns of the two effects, which limit their universality and effectiveness. Therefore, this paper integrates the radial inertia effect and friction effect in a unified deformation framework through reasonable assumptions, and proposes a method to correct the specimen from a complex stress state to a uniaxial stress state. SHPB numerical simulation experiments demonstrate that this method effectively eliminates the combined effects of radial inertia and friction on measurement results for both elastic and viscoelastic materials, including the size effect associated with these two factors. Additionally, the paper presents a scheme to determine the friction coefficient using the size effect of the specimens when the friction coefficient between the specimen and the bar is unknown. Finally, the method was applied to correct the stresses measured in SHPB experiments on silicone rubber of different diameters. It successfully eliminated discrepancies in the stress-strain relationships between specimens of various sizes and determined a friction coefficient that fell within a reasonable range.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A hybrid data-driven machine learning framework for predicting the impact resistance of composite armor 用于预测复合装甲抗冲击性的混合数据驱动机器学习框架

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-19 DOI: 10.1016/j.ijimpeng.2024.105125

{"title":"A hybrid data-driven machine learning framework for predicting the impact resistance of composite armor","authors":"","doi":"10.1016/j.ijimpeng.2024.105125","DOIUrl":"10.1016/j.ijimpeng.2024.105125","url":null,"abstract":"<div><div>Composite armor plays a crucial role as the primary defense against high-velocity impacts from fragments and projectiles. However, balancing the need for lightweight structures with the requirement for robust protection remains a significant engineering challenge. Traditional approaches for predicting the protective performance of armor typically involve a combination of experimental testing and numerical simulations, both of which can be resource-intensive and costly. In contrast, data-driven methods combined with machine learning have demonstrated the potential to significantly reduce both time and economic costs, highlighting their substantial advantages in various engineering domains. Unfortunately, a mature machine learning framework for predicting the performance of multilayer composite armor against high-velocity impacts from large fragments has yet to be established. In this paper, a novel data-driven framework for predicting the ballistic performance of composite armor using a hybrid model of Support Vector Machine and Deep Neural Network was established. This framework employed hyperparameter optimization to enhance predictive performance, yielding a model with excellent accuracy. The proposed model was adaptable to multilayered armor with varying layer thicknesses, enabling rapid predictions of armor penetration, residual projectile kinetic energy, and armor deformation.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0734743X24002501/pdfft?md5=edad608188e164a3bc4026d92471f9d4&pid=1-s2.0-S0734743X24002501-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142312177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A graph network-based learnable simulator for spatial-temporal prediction of rigid projectile penetration 基于图网络的可学习模拟器，用于硬质射弹穿透的时空预测

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-19 DOI: 10.1016/j.ijimpeng.2024.105123

{"title":"A graph network-based learnable simulator for spatial-temporal prediction of rigid projectile penetration","authors":"","doi":"10.1016/j.ijimpeng.2024.105123","DOIUrl":"10.1016/j.ijimpeng.2024.105123","url":null,"abstract":"<div><div>Predicting plate penetration by rigid projectiles (PPRP) is crucial in terminal ballistics, with broad applications in civil and military engineering. Empirical and analytical methods face challenges in predicting field variables like displacement and stress in target plates. Although numerical methods offer high accuracy, they suffer from low computational efficiency. Herein, we introduce an efficient data-driven machine learning (ML) method based on graph neural networks (GNNs), named PGN, specifically tailored to address the PPRP problem. Unlike traditional ML methods that establish direct input-output mappings, PGN predicts comprehensive spatial-temporal information pertaining to the projectile-target interaction process. A thorough analysis of PGN's performance in terms of accuracy, computational efficiency and generalization ability was performed. Compared to validated results of numerical simulations, PGN maintained high precision with RMSE for displacement, stress, and strain predictions below 0.5 %, 9.5 %, and 2.1 %, respectively. It also achieved <em>R</em><sup>2</sup> values exceeding 0.92 for the time history of projectile velocity and acceleration, while requiring only 9.8 % of the computation time compared to LS-DYNA. In generalization tests, PGN exhibited remarkable adaptability in tackling challenging scenarios that extend far beyond the training data distribution, with overall RMSE between 11 % and 13 %. Furthermore, we find that the maximum information propagation capacity of a simulated physical system must meet or exceed the information propagation need of the real-world physical phenomenon it aims to replicate. Consequently, an approach was proposed to determine the critical connectivity radius of the massage passing method directly from the wave speed in the target medium, which greatly improved the accuracy and efficiency of PGN.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact response of additively manufactured density-graded open-cell foams 加成型密度分级开孔泡沫的冲击响应

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-19 DOI: 10.1016/j.ijimpeng.2024.105127

{"title":"Impact response of additively manufactured density-graded open-cell foams","authors":"","doi":"10.1016/j.ijimpeng.2024.105127","DOIUrl":"10.1016/j.ijimpeng.2024.105127","url":null,"abstract":"<div><div>Additive manufacturing has made it possible to fabricate materials that were unachievable with traditional methods. This study focuses on understanding the deformation behavior and energy absorption mechanics of additively manufactured cellular materials with gradually varying densities. Foams have unique deformation behavior due to their intricate topology and composition, resulting in excellent energy dissipation capability. Varying the density can significantly influence their deformation response and improve energy absorption and impact resistance. Voronoi tessellation is employed to model the foams, as it effectively captures the cell morphology in foam structures and produces stochastic cellular topologies accurately. Resin-based additive manufacturing techniques are employed to fabricate cellular materials with varying density configurations for low-velocity and high-velocity impact experiments. The study demonstrates that density-graded foams effectively dissipate a broad spectrum of impact energies, surpassing uniform counterparts by transmitting reduced stress, especially at lower energy levels. This characteristic enhances their suitability for advanced energy absorption applications. The results also show that at high impact velocities, the direction of density gradation influences energy dissipation and peak stress transmission.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Strain rate sensitivity of rotating-square auxetic metamaterials 旋转方形辅助超材料的应变速率敏感性

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-19 DOI: 10.1016/j.ijimpeng.2024.105128

{"title":"Strain rate sensitivity of rotating-square auxetic metamaterials","authors":"","doi":"10.1016/j.ijimpeng.2024.105128","DOIUrl":"10.1016/j.ijimpeng.2024.105128","url":null,"abstract":"<div><div>This study provides an in-depth analysis of the mechanical behavior of rotating-square auxetic structures under various strain rates. The structures are fabricated using stereolithography additive manufacturing with a flexible resin. Mechanical tests performed on structures include quasi-static, intermediate, and high strain rate compression tests, supplemented by high-speed optical imaging and two-dimensional digital image correlation analyses. In quasi-static conditions (5 × 10<sup>–3</sup> s<sup>-1</sup>), multiscale measurements reveal the correlation between local and global strains. It is shown that cell hinges play a significant role in structural deformation and load-bearing capacity. In drop tower impact conditions (intermediate strain rate of <em>ca.</em> 200 s<sup>-1</sup>), the auxetic structures display significant strain rate hardening compared to loading at quasi-static rates. The thin-hinge structures maintain a Poisson's ratio of approximately -0.8, showing higher auxeticity than slow-rate compression tests. High strain rate conditions (<em>ca.</em> 2000s<sup>-1</sup>) activate additional deformation mechanisms, including a delayed state of equilibrium exemplified by a heterogeneous distribution of lateral strains, possibly due to stress wave interactions and inertial stresses. The study further reveals nonlinear correlations between Poisson's ratio, strain, and strain rate, indicating reduced auxeticity at higher strain rates. These observations are discussed in terms of complex wave interactions and the strain rate hardening characteristics of the base polymer.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0734743X24002537/pdfft?md5=a22ffdd931554c28f73c2b7ce3fda3e7&pid=1-s2.0-S0734743X24002537-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142312176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Molecular dynamics-informed material point method for hypervelocity impact analysis 用于超高速撞击分析的分子动力学信息材料点法

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-16 DOI: 10.1016/j.ijimpeng.2024.105124

引用次数: 0

Occurrence phase of peak responses to symmetric pulse loads 对称脉冲负载峰值响应的出现阶段

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-14 DOI: 10.1016/j.ijimpeng.2024.105122

{"title":"Occurrence phase of peak responses to symmetric pulse loads","authors":"","doi":"10.1016/j.ijimpeng.2024.105122","DOIUrl":"10.1016/j.ijimpeng.2024.105122","url":null,"abstract":"<div><p>This study fills a challenging gap in the field of structural dynamics. A potential rule is theoretically proved: The peak displacements of undamped single-degree-of-freedom (SDOF) systems subjected to nonnegative but symmetric pulse loads necessarily occur within the pulse loading duration if the frequency ratio <span><math><mrow><mi>β</mi><mo><</mo></mrow></math></span>1, and after the pulse loading duration if the frequency ratio <span><math><mi>β</mi></math></span>>1. As a special case, the first peak displacements accurately take place at the end of the pulse loading when <span><math><mi>β</mi></math></span>=1. Also, the occurrence time of the first peak displacements has a theoretic value of <span><math><msub><mi>t</mi><mi>ϕ</mi></msub></math></span>=<span><math><msub><mi>t</mi><mi>p</mi></msub></math></span>/2+<span><math><mi>T</mi></math></span>/4 in the case of <span><math><mi>β</mi></math></span>>1. Although this potential rule can be easily verified in certain cases, it has not been theoretically and systematically proved so far. A rigorous and complete proof is presented and featured by the proposed analysis based on Duhamel's integral. The analyzation circumvents the difficulties in analytically solving dynamic responses to different pulse loads in different shapes, but still reaches theoretical conclusions and yields a general law of structural dynamics. The proved law can be used to predict the occurrence phase of the first peak displacements when undamped SDOF systems subjected to nonnegative but symmetric pulse loads.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0734743X24002471/pdfft?md5=244cb013c15d338960301f2273efa8ec&pid=1-s2.0-S0734743X24002471-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142274565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analytical and numerical models to predict the shape of incident pulse in split-Hopkinson bar experiments 预测分裂霍普金森棒实验中入射脉冲形状的分析和数值模型

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-14 DOI: 10.1016/j.ijimpeng.2024.105103

{"title":"Analytical and numerical models to predict the shape of incident pulse in split-Hopkinson bar experiments","authors":"","doi":"10.1016/j.ijimpeng.2024.105103","DOIUrl":"10.1016/j.ijimpeng.2024.105103","url":null,"abstract":"<div><div>In typical split-Hopkinson pressure bar experiments (SHPB), the striker bar impacts the incident bar via discs made from soft materials such as copper. These discs, also called pulse shapers, are used (i) to eliminate the high frequency components of the incident pulse, (ii) to obtain a finite rise time of the incident pulse and (iii) to obtain a constant strain rate. Although these pulse shapers have been used for over decades in SHPB experiments, no analytical solutions or simple models are available that can predict the incident pulse as a function of the striker velocity, pulse shaper geometry and material parameters. Assuming that the pulse shaper is a rigid-linearly hardening material, we derive the analytical solution for the incident pulse when the rise time of the incident pulse is less than twice the time taken for a longitudinal wave to travel along the length of the striker. For larger rise times, we additionally assume that the striker is rigid to obtain a simple numerical model to predict the incident pulse in the presence of a pulse shaper. Both these models are validated against numerical simulations and experiments to demonstrate their accuracy.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142427799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental study on the blast resistance of polyurea-coated aramid fabrics 聚脲涂层芳纶织物抗爆性实验研究

IF 5.1 2区工程技术

International Journal of Impact Engineering Pub Date : 2024-09-12 DOI: 10.1016/j.ijimpeng.2024.105120

{"title":"Experimental study on the blast resistance of polyurea-coated aramid fabrics","authors":"","doi":"10.1016/j.ijimpeng.2024.105120","DOIUrl":"10.1016/j.ijimpeng.2024.105120","url":null,"abstract":"<div><p>This paper investigates overpressure attenuation capacity and failure mechanism of the polyurea-coated aramid fabric (PCAF) subjected to air-blast loading experimentally. The peak overpressure, arrival time and positive pressure duration of shock waves on the blast and back side of PCAFs were obtained in tests and analyzed. In addition, the failure mode and mechanism were revealed with the electron scanning microscope (SEM), meanwhile the effect of polyurea type, coating position and thickness ratio on the blast resistance were discussed. The results show that in the cases of scaled distances of 1.84 and 2.32 m/kg<sup>1/3</sup>, PCAFs, one-layer polyurea coated on three-layer aramid woven fabrics, can attenuate the peak overpressure by about 70 %, delay the arrival time by about 0.7 ms, and shorten the positive pressure duration by 10 %-50 %. This is due to the increased out-of plane stiffness and closure of interweaving apertures of the aramid fabric. Furthermore, perforation is the main failure mode of aramid fabrics, in which the tensile breakage in weft yarn and the frictional slip in warp yarn, while the failure modes of PCAF mainly include fracture and exfoliation, with both weft and warp yarns breakage and polyurea failure. It was concluded that the degree of infiltration between the polyurea and fabric affects mechanical properties of the fiber, changing the failure mode of PCAF. In terms of the extent of damage, the PCAF exhibits a superior blast resistance when the polyurea coated on the back side. The blast resistance of PCAF increases first then decreases with an increase in the thickness of the polyurea layer under the same areal density.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0734743X24002458/pdfft?md5=8d485b9d23fde721efed0ed71e401722&pid=1-s2.0-S0734743X24002458-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142230229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0