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Defence Technology（防务技术） 2023年第3期21卷 184-195页

作者： Chao Ge Die Hu Jin Wang Qingbo Yu Haifu Wang Yuanfeng Zheng School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China

To investigate the thermal response and initiation behavior of ternary fluoropolymer-matrix PTFE/Al/W reactive materials,a research combining shock loading tests and trans-scale modelling is conducted.On the basis of a good agreement of the numerically simulated and tested shock wave propagation,the significant impact of component ratios and particle sizes on the evolution of mesoscopic temperature,hot-spots and initiation is well characterized and analyzed.Results demonstrate that as the content of W increases,the range of mesoscopic high-temperature area increases and tends to distribute more uniform,while material with smaller W particles causes more intense particle deformation and larger temperature rise.The time to reach the critical temperature shows positive correlation to the content of W,while the critical temperature of hot-spots shows negative correlation to the particle size of W.For PTFE/Al/W of high density,with the increase of W particle size,the reaction rate decrease,however the time to reach the peak reaction rate shortens.

关键词： deformation shock loading

Constructing self-supporting surfaces with planar quadrilateral elements

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Computational Visual Media 2022年第4期8卷 571-583页

作者： Long Ma Sidan Yao Jianmin zheng Yang Liu yuanfeng Zhou Shi-Qing Xin Ying He School of Software Shandong UniversityJinan 250101China School of Computer Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Internet Graphics Group Microsoft Research AsiaBeijing 100080China School of Computer Science and Technology Shandong UniversityQingdao 266237China

We present a simple yet effective method for constructing 3D self-supporting surfaces with planar quadrilateral(PQ)elements.Starting with a triangular discretization of a self-supporting surface,we firstcompute the principal curvatures and directions of each triangular face using a new discrete differential geometryapproach,yielding more accurate results than existing methods.Then,we smooth the principal direction field to reduce the number of singularities.Next,we partition all faces into two groups in terms of principalcurvature difference.For each face with small curvature difference,we compute a stretch matrix that turns the principal directions into a pair of conjugate directions.For the remaining triangular faces,we simply keep their smoothed principal directions.Finally,applying a mixed-integer programming solver to the mixed principal and conjugate direction field,we obtain a planar quadrilateral mesh.Experimental results show that our method is computationally efficient and can yield high-quality PQ meshes that well approximate the geometry of the input surfaces and maintain their self-supporting properties.

关键词： self-supporting surfaces planar quadri-lateral(PQ)meshes conjugate direction fields(CDFs)

Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability

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Defence Technology（防务技术） 2024年第2期32卷 242-253页

作者： Tao Sun Haifu Wang Shipeng Wang Chao Ge Die Hu Pengwan Chen Yuanfeng Zheng Beijing Institute of Technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China Xi'an Institute of Electromechanical Information Technology Xi'an710065China

Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical simulations.The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used.Three types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and tested.The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over time.Moreover,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact.From simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy cluster.The unique formation structure determines the damage modes of the aluminum plate and the steel plate.Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content.With increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration.However,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

关键词： Reactive materials Al-PTFE composites Reactive liner X-ray Penetration

Enhanced structural damage behavior of liquid-filled tank by reactive material projectile impact

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Defence Technology（防务技术） 2024年第1期31卷 211-229页

作者： Jianwen Xie Yuanfeng Zheng Zhenyang Liu Chengzhe Liu Aoxin Liu Pengwan Chen Haifu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was studied in detail.PTFE/Al/W RMPs with steel-like and aluminum-like densities were prepared by a pressing/sintering process.The projectiles impacted a liquid-filled steel tank with front aluminum panel at approximately 1250 m/s.The corresponding cavity evolution characteristics and HRAM pressure were recorded by high-speed camera and pressure acquisition system,and further compared to those of steel and aluminum projectiles.Significantly different from the conical cavity formed by the inert metal projectile,the cavity formed by the RMP appeared as an ellipsoid with a conical front.The RMPs were demonstrated to enhance the radial growth velocity of cavity,the global HRAM pressure amplitude and the front panel damage,indicating the enhanced HRAM and structural damage behavior.Furthermore,combining the impact-induced fragmentation and deflagration characteristics,the cavity evolution of RMPs under the combined effect of kinetic energy impact and chemical energy release was analyzed.The mechanism of enhanced HRAM pressure induced by the RMPs was further revealed based on the theoretical model of the initial impact wave and the impulse analysis.Finally,the linear correlation between the deformation-thickness ratio and the non-dimensional impulse for the front panel was obtained and analyzed.It was determined that the enhanced near-field impulse induced by the RMPs was the dominant reason for the enhanced structural damage behavior.

关键词： Reactive material projectile Hydrodynamic ram Enhanced structural damage Liquid-filled tank Impact

Experimental study and simulation of a three-phase flow stirred bioreactor

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Chinese Journal of Chemical Engineering 2019年第3期27卷 649-659页

作者： Chenghui zheng Jiashun Guo Chengkai Wang yuanfeng Chen Huidong zheng Zuoyi Yan Qinggen Chen School of Chemical Engineering Fuzhou University Fujian Provincial Academy of Environmental Science Xiamen Zijin Mining & Metallurgy Technology Co.Ltd.

In order to obtain the reasonable operating conditions and minimize the power consumption in the stirred bioreactor, the hydrodynamic experiments in the stirred bioreactor have been taken to obtain the basic data. Subsequently, an Eulerian model for the gas–liquid–solid three phase flow in the stirred bioreactor has been proposed and the CFD simulation has been conducted. By comparing the results of experiment and simulation, it can be concluded that the simulation results were consistent with the experimental data. The inner relationship between operating variables and indicators could be obtained by comparing the results of just suspension speed, gas holdup, power consumption and operational maps, further the reasonable operating conditions could be also determined under the minimum power consumption. The operational maps could provide the theoretical foundation for industrial application of the gas–liquid–solid stirred bioreactors under the low solid concentration(no more than 20 wt%).

关键词： Stirred bioreactor Hydrodynamics experiment Simulations Operational maps

Mathcad在钢筋混凝土梁斜截面受剪承载力计算中的应用

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淮北职业技术学院学报 2020年第3期19卷 102-106页

作者：郑元锋福建水利电力职业技术学院建筑工程系福建永安366000

根据钢筋混凝土梁斜截面受剪承载力的计算公式与计算步骤,采用Mathcad软件的编程方法快速计算梁的箍筋间距、验算梁的配箍率,通过不同类型的实例验证Mathcad编程设计的计算结果。

关键词： Mathcad 钢筋混凝土梁受剪承载力箍筋配箍率

MathCAD在钢筋混凝土轴心受压构件承载力计算中应用

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襄阳职业技术学院学报 2020年第3期19卷 89-93页

作者：郑元锋福建水利电力职业技术学院福建永安366000

基于钢筋混凝土轴心受压构件正截面承载力的计算原理与计算步骤,采用MathCAD软件进行编程,精确计算矩形截面钢筋混凝土轴心受压构件正截面承载力,并验算选配钢筋的配筋率,最后通过各种不同条件的实例来显示MathCAD编程计算结果。

关键词： MathCAD 轴心受压构件承载力计算受压钢筋计算面积配筋率

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钢筋绑扎安装实训中常见问题及分析

襄阳职业技术学院学报 2019年第6期18卷 67-69,83页

作者：郑元锋福建水利电力职业技术学院

文章介绍了建筑工程技术专业钢筋绑扎安装实训模块,重点分析学生在钢筋绑扎安装实训中常见的问题及原因,为今后开展钢筋绑扎安装实训的学生或指导教师提供参考或借鉴。

关键词：钢筋绑扎与安装绑扎方法框架梁独立基础

活性药型罩聚能装药侵彻爆燃试验及耦合作用机理分析

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兵工学报 2023年第2期44卷 334-344页

作者：苏成海李宗谕郑元枫郑志坚郭焕果北京理工大学爆炸科学与技术国家重点实验室北京100081 保利澳瑞凯(山东)矿业服务有限公司山东威海264200

为研究氟聚物基活性药型罩聚能装药对钢靶的侵彻爆燃行为及耦合作用机理,开展配方为质量分数73.5%聚四氟乙烯(PTFE)/26.5%Al活性药型罩聚能装药作用钢靶静爆实验,获得炸高对侵彻深度、侵彻孔径、钢靶爆裂行为影响特性。实验结果表明,活... 详细信息

为研究氟聚物基活性药型罩聚能装药对钢靶的侵彻爆燃行为及耦合作用机理,开展配方为质量分数73.5%聚四氟乙烯(PTFE)/26.5%Al活性药型罩聚能装药作用钢靶静爆实验,获得炸高对侵彻深度、侵彻孔径、钢靶爆裂行为影响特性。实验结果表明,活性药型罩聚能装药炸高在0.35~1.00倍装药直径范围内,对钢靶侵爆耦合毁伤效应最为显著。结合准定常理想不可压缩流体力学理论,引入活性射流反应延迟时间,给出活性射流侵彻深度与反应延迟时间函数关系,建立活性射流侵孔内有效质量模型;基于修正的伯努利方程,结合活性射流内爆特性,发展活性射流侵孔孔径理论模型;结合圆筒破坏理论提出活性射流侵爆耦合作用下钢靶爆裂行为判断方法。理论模型定量化描述了活性射流对钢靶的侵爆行为,揭示了破甲终止后活性射流内爆超压导致的扩孔与钢靶爆裂机理。

关键词：活性材料活性药型罩侵彻爆燃毁伤模型

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一种基于弱监督学习的图像镜面高光去除算法

信号处理 2023年第6期39卷 1016-1024页

作者：郑元丰张威江昊华光武汉大学电子信息学院湖北武汉430072

高质量图像是计算机视觉任务的基础,但实际生活中高光的出现会覆盖物体表面的纹理和颜色信息,导致图像质量显著下降。目前用于高光去除的深度学习方法往往需要大量高光-无高光配对图像进行监督,而高光图像对应的无高光版本存在收集和处... 详细信息

高质量图像是计算机视觉任务的基础,但实际生活中高光的出现会覆盖物体表面的纹理和颜色信息,导致图像质量显著下降。目前用于高光去除的深度学习方法往往需要大量高光-无高光配对图像进行监督,而高光图像对应的无高光版本存在收集和处理困难的问题。本文提出一种基于弱监督学习的图像镜面高光去除算法,旨在仅使用高光图像完成训练且达到很好的高光去除效果。首先,利用稀疏非负矩阵分解(NMF)方法估计图像的高光区域,并从无高光区域裁剪出无高光的参考图像。然后,将两者输入到联合训练的高光生成、高光消除和图像重建模块,协同优化各模块功能。总体采用循环生成对抗网络(CycleGAN)架构训练网络并最终生成无高光图像。选取自然图像数据集SHIQ和LIME进行实验,实验结果表明,所提方法能够有效去除镜面高光,并且在性能上对比现有的弱监督学习方法有较大提升。

关键词：镜面高光去除循环生成对抗网络弱监督学习稀疏非负矩阵分解