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Ballistic performance of additive manufacturing 316l stainless steel projectiles based on topology optimization method

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Defence Technology（防务技术） 2024年第5期35卷 1-17页

作者： Hao Xue Tao Wang Xinyu Cui Yifan Wang guangyan huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Material and structure made by additive manufacturing(AM)have received much attention lately due to their flexibility and ability to customize complex *** study first implements multiple objective topology optimization simulations based on a projectile perforation model,and a new topologic projectile is *** two types of 316L stainless steel projectiles(the solid and the topology)are printed in a selective laser melt(SLM)machine to evaluate the penetration performance of the projectiles by the ballistic *** experiment results show that the dimensionless specific kinetic energy value of topologic projectiles is higher than that of solid projectiles,indicating the better penetration ability of the topologic ***,microscopic studies(scanning electron microscope and X-ray micro-CT)are performed on the remaining projectiles to investigate the failure mechanism of the internal structure of the topologic *** explicit dynamics simulation was also performed,and the failure locations of the residual topologic projectiles were in good agreement with the experimental results,which can better guide the design of new projectiles combining AM and topology optimization in the future.

关键词： Additive manufacturing Topology optimization Ballistic performance Projectile design

A novel nest-based scheduling method for mobile wireless body area networks

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Digital Communications and Networks 2020年第4期6卷 514-523页

作者： Zhijun Xie guangyan huang Roozbeh Zarei Zhenyan Ji Hongwu Ye Jing He Department of Information Science and Engineering Ningbo UniversityNingboChina School of Information Technology Deakin UniversityMelbourneAustralia Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingboChina School of Software Engineering Beijing Jiaotong UniversityBeijingChina Zhejiang Fashion Institute of Technology NingboChina Institute of Information Technology Nanjing University of Finance and EconomicsJiangsuNanjingChina Swinburne Data Science Research Institute Swinburne University of TechnologyMelbourneAustralia

Wireless Body Area Networks(WBANs)comprise various sensors to monitor and collect various vital signals,such as blood pressure,pulse,heartbeat,body temperature,and blood sugar.A dense and mobile WBAN often suffers from interference,which causes serious problems,such as wasting energy and degrading *** reality,not all of the sensors in WBAN need to be active at the same ***,they can be divided into different groups so that each group works in turn to avoid *** this paper,a Nest-Based WBAN Scheduling(NBWS)algorithm is proposed to cluster sensors of the same types in a single or multiple WBANs into different groups to avoid ***,we borrow the graph coloring theory to schedule all groups to work using a Time Division for Multimodal Sensor(TDMS)group scheduling *** theoretical analysis and experimental results demonstrate that the proposed NBWS algorithm performs better in terms of frequency of collisions,transmission delay,system throughput,and energy consumption compared to the counterpart methods.

关键词： Interference elimination Nest Sensors Scheduling Wireless body area networks Graph coloring theory

组合载荷下含缺口纤维增强树脂基复合材料的失效分析

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复合材料学报 2018年第10期35卷 2723-2729页

作者：曹倩妮刘广彦黄广炎北京理工大学宇航学院力学系北京100081 北京理工大学机电学院爆炸科学与技术国家重点实验室北京100081

为研究含缺口纤维增强复合材料层合板在复杂载荷下的破坏,本文采用改进的Arcan夹具,在30°方向对含缺口碳纤维增强树脂基复合材料层合板([-45/90/45/0]s)进行了拉伸-剪切组合加载实验。用数字图像相关方法(DICM)测量了层合板表面层的裂... 详细信息

为研究含缺口纤维增强复合材料层合板在复杂载荷下的破坏,本文采用改进的Arcan夹具,在30°方向对含缺口碳纤维增强树脂基复合材料层合板([-45/90/45/0]s)进行了拉伸-剪切组合加载实验。用数字图像相关方法(DICM)测量了层合板表面层的裂纹发展过程,在缺口尖端观察到了明显的劈裂现象。然后用有限元软件ABAQUS建立了三维层合板模型,为准确模拟裂纹尖端的应力场,模型中每层引入内聚力接触来模拟劈裂。为了比较加载端的转动自由度对层合板失效模式和破坏强度的影响,文中分析了两种不同的边界条件,即约束和放松加载端的转动自由度。研究结果发现,加载端的合力方向主导了层合板的失效模式和破坏强度,放松加载端自由度的模拟结果与实验结果有很好的一致性。

关键词： Arcan夹具组合加载数字图像相关内聚力接触边界条件

Clinical study on eye metastasis in patients with breast cancer

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Chinese Medical Journal 2014年第5期127卷 961-967页

作者： Ji guangyan Xing Lei huang Jianbo Kong Lingquan Wang Ziwei Ren Guosheng Wu Kainan Department of General Surgery First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China

Metastasis is one of the most common manifestations of *** the treatment options and life expectancy of the cancer patients are improving,the numbers of different metastatic lesions,including those uncommon metastatic sites are expected to *** metastasis from carcinoma,which is the most common type of ocular malignancy in adults,is found in an increasing number of patients,mostly with breast and lung cancer.

关键词： breast cancer choroidal metastasis treatment eyes examination

Treatment of facial palsy after parotid tumor surgery by great auricular nerve grafting

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中国口腔颌面外科杂志 2008年第B5期6卷 73-74页

作者： Lu Xuguang Cai Zhigang Yu guangyan Peng Xin huang Minxian Peking University Hospital & School of Stomatology Department of Maxillofacial Surgery Zhongguancun South Street 22th H aidian District Beijing 100083 China

INSTANTANEOUS DOPPLER FREQUENCY FOR SQUINT SAR IMAGING

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Journal of Electronics(China) 2003年第5期20卷 337-343页

作者： Liu guangyan huang Shunji (Dept. of Electron. Eng., UEST of China, Chengdu 610054) Dept. of Electron. Eng. UEST of China Chengdu

Instantaneous Doppler frequency for squint SAR imaging has been found with ChirpScaling Algorithm (CSA). Because the azimuth sample is not perpendicular to the range sample,the range signal must impact on the azimuth signal in the squint SAR data processing, andthe different slant range targets have different Doppler frequencies. From the mathematicalmodel of SAR echo signal, this paper carefully analyzes the instantaneous azimuth frequency, theinstantaneous Doppler frequency component of the azimuth frequency and the impact of rangechirp on azimuth frequency, which explains that Doppler frequency should be properly selected forcorrect SAR imaging in the squint SAR. The results of point target simulation experiments showthat the way is reasonable for the squint SAR and can effectively complete range compressionand azimuth focusing, and improve images' quality.

关键词： PRF Doppler frequency Chirp scaling algorithm Range chirp rate SAR

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典型防爆装备对TNT爆炸冲击波的防护性能

兵工学报 2023年第10期44卷 2871-2884页

作者：杨磊刘瀚黄广炎田相鹏北京理工大学爆炸科学与技术国家重点实验室北京100081 北京理工大学重庆创新中心重庆401120

爆炸冲击波是炸药爆炸时产生的强间断载荷,是引起人体颅脑、肺部等含气器官组织直接损伤的主导危害。基于Q235钢钢材和复合材料+液体两种典型材质的防爆装备,开展多种TNT药量的静爆试验和数值计算,研究空爆(FAB)、钢制防爆罐(SEP)和柔... 详细信息

爆炸冲击波是炸药爆炸时产生的强间断载荷,是引起人体颅脑、肺部等含气器官组织直接损伤的主导危害。基于Q235钢钢材和复合材料+液体两种典型材质的防爆装备,开展多种TNT药量的静爆试验和数值计算,研究空爆(FAB)、钢制防爆罐(SEP)和柔性防爆罐(FEP)3种不同防护条件下冲击波传播衰减规律,分析SEP和FEP两种典型防爆装备的响应过程与防护机理,获得典型装备冲击波超压峰值削弱防护的经验模型。研究结果表明:SEP和FEP可以大幅度削弱内爆炸冲击波载荷,相较于同位置处的FAB,SEP可削弱冲击波超压峰值55.4%~66.3%,FEP可削弱超压峰值57.2%~77.7%,且过当量爆炸时FEP的冲击波防护能力明显高于SEP;分析SEP和FEP的主要防护机理均为绕射遮蔽作用,但FEP的顶盖显著增加了冲击波与结构作用时间,通过水的动量提取效应和不同波阻抗界面反射削弱逃逸冲击波强度,而SEP中的冲击波仅通过刚性材料反射消耗后迅速绕射逃逸;建立了SEP、FEP冲击波峰值超压削弱经验模型,与试验结果相比SEP、FEP削弱模型平均误差分别为2.4%和10.2%;得到的典型装备冲击波削弱规律及防护经验模型为防爆罐装备设计提供了参考。

关键词：爆炸防护防爆装备冲击波超压经验模型

氧化锌改性芳纶织物的抗弹道冲击性能的数值模拟

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兵工学报 2023年第10期44卷 2897-2905页

作者：许尧杰刘瀚张宏黄广炎北京理工大学爆炸科学与技术国家重点实验室北京100081 北京理工大学重庆创新中心重庆401120

芳纶织物由于其低密度、高模量、高强度特性被广泛应用于人体防弹领域,为提高芳纶织物的抗弹性能,通过纳米氧化锌颗粒种植生长对芳纶织物进行改性,开展电镜观察、准静态拉伸试验、纱线拉拔试验、弹道冲击试验和数值模拟工作,得到了氧化... 详细信息

芳纶织物由于其低密度、高模量、高强度特性被广泛应用于人体防弹领域,为提高芳纶织物的抗弹性能,通过纳米氧化锌颗粒种植生长对芳纶织物进行改性,开展电镜观察、准静态拉伸试验、纱线拉拔试验、弹道冲击试验和数值模拟工作,得到了氧化锌改性织物的力学性能和弹道性能。研究结果表明:氧化锌颗粒的种植增加了纤维之间的结构互锁与表面粗糙度,氧化锌改性织物的纱线间摩擦系数较纯织物提高了282%,弹道极限速度较纯织物提高了54.5%,且吸能与比吸能性能显著优于纯织物;通过细观纱线模型对织物的弹道冲击过程进行模拟,仿真结果与弹道试验结果具有良好的一致性,进一步说明了纱线间摩擦系数和拉伸强度的提升可以作为提高织物的抗弹道冲击性能的有效手段,为氧化锌改性织物在柔性防弹领域的应用提供了理论依据。

关键词：芳纶织物氧化锌改性弹道极限数值模拟

弹道冲击下石墨烯和聚乙烯改性芳纶织物的钝伤防护性能

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兵工学报 2024年第1期45卷 35-43页

作者：王哲刘鹏陈婧黄广炎张宏北京理工大学爆炸科学与技术国家重点实验室北京100081 北京理工大学重庆创新中心现代兵器技术实验室重庆401120

芳纶凭借其轻质高强的特点广泛应用于防弹领域。为提高单层芳纶织物的抗钝伤能力,采用热塑性树脂聚乙烯(Polythene,PE)与石墨烯纳米粒子表面改性方法提升芳纶织物的抗钝伤性能。以背衬凹陷为标准,对不同质量配比改性芳纶织物的抗钝伤能... 详细信息

芳纶凭借其轻质高强的特点广泛应用于防弹领域。为提高单层芳纶织物的抗钝伤能力,采用热塑性树脂聚乙烯(Polythene,PE)与石墨烯纳米粒子表面改性方法提升芳纶织物的抗钝伤性能。以背衬凹陷为标准,对不同质量配比改性芳纶织物的抗钝伤能力和能量吸收特性进行测试对比。对比结果表明:石墨烯和PE两种改性方法均可提升芳纶织物的抗钝伤能力,其中PE改性方法使得改性织物面密度增加较小但抗钝伤能力显著提升,10%PE的防弹能力和比吸能值较纯芳纶分别提升了18.0%和30.8%;石墨烯改性织物刚性的增加使其低速抗钝伤能力增强,但是过大的纱线间摩擦使其高速防护能力减弱,2%石墨烯粉体为石墨烯改性织物的最佳配比。此外,优化验证得到了2层10%PE和13层的6层正交超高分子量PE无纬布防弹衣组合设计。

关键词：改性芳纶织物钝伤防护背衬凹陷防弹性能能量吸收

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