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某串联战斗部级间隔爆体结构的优化设计

兵器装备工程学报 2024年第S1期45卷 170-175页

作者：龚宏杰余瑞郭翔唐昌州王志昊杜黎小松金路轩李忠友航天化学动力技术重点实验室湖北襄阳441003 湖北航天化学技术研究所湖北襄阳441003

为实现串联战斗部级间隔爆体结构减重,利用有限元分析软件LS-DYNA建立了某型前级战斗部与隔爆体的数值仿真模型,采用正交试验的方法,研究级间锥形隔爆体前锥角,倒角与前后锥角差值对隔爆体质量的影响规律。结果表明:隔爆体的前锥角对隔... 详细信息

为实现串联战斗部级间隔爆体结构减重,利用有限元分析软件LS-DYNA建立了某型前级战斗部与隔爆体的数值仿真模型,采用正交试验的方法,研究级间锥形隔爆体前锥角,倒角与前后锥角差值对隔爆体质量的影响规律。结果表明:隔爆体的前锥角对隔爆体质量影响显著,前后锥角差次之,倒角影响较弱。利用正交优化方法,设计三因素四水平的正交优化方案,结果表明当,r=9.9 mm,时,隔爆体的质量最低为485.40 g。研究成果可为串联战斗部隔爆体的结构设计和优化提供指导。

关键词：串联战斗部隔爆体数值仿真正交优化结构减重

热感觉对气候温和地区热舒适模型的修正作用研究

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科技通报 2024年第8期40卷 45-50页

作者：李游雅张枫付婷王志浩邓诗涵昆明理工大学建筑工程学院昆明650031

为探究气候温和地区高校教室内的热舒适性,且修正预测热感觉和不满意度模型(predicted mean vote-predicted percentage of dissatisfaction,PMV-PPD模型)与实际热感觉投票值存在偏差情况,本文以昆明某高校大学生受试者为试验对象,分别... 详细信息

为探究气候温和地区高校教室内的热舒适性,且修正预测热感觉和不满意度模型(predicted mean vote-predicted percentage of dissatisfaction,PMV-PPD模型)与实际热感觉投票值存在偏差情况,本文以昆明某高校大学生受试者为试验对象,分别测试室内环境参数、人员评估环境温度(t_(1))以及受试者主观评价等,共获得2229份有效数据。结果表明:在自然通风教室中,超过80%的大学生可以接受当前的热湿环境,PMV与实际平均热感觉投票(mean thermal sensation,MTS)模型相关较弱,PMV模型高估了受试者的实际热感觉,实测人员不满意百分比普遍大于预测不满意百分比。鉴于PMV模型预测准确性较低,综合考虑温度变化、主观反应等影响因素,提出人员评估环境温度(t_(1))作为修正性指标。人员评估环境温度与实际环境温度存在较强相关性,且在不同场景中两者温差值小于1.5℃。将t_(1)与热感觉投票进行回归分析,该参数与热感觉投票高度相关。在PMV计算中使用t_(1)代替空气温度对PMV模型进行修正得到tPMV,修正后的tPMV更接近于MTS模型,对PMV起到显著有效的修正作用。

关键词：热感觉 PMV-PPD模型温和地区热舒适模型修正

Electrolyte-gated SrCoO_(x) FET sensor for highly sensitive detecting pH in extreme alkalinity solution

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Nano Research 2024年第4期17卷 3079-3086页

作者： Han Zhou Gaocan Qi Wenbin Li Yuhang wang zhihao Yuan School of Materials Science and Engineering Tianjin Key Lab of Photoelectric Materials&Devicesand Key Laboratory of Display Materials and Photoelectric Devices(Ministry of Education)Tianjin University of TechnologyTianjin 300384China

The pH monitoring is significantly important in chemical industry,biological process,and pollution ***,it remains a great challenge to measure pH in extreme alkalinity ***,we employ an electrolyte-gated field-effect-transistor(FET)strategy using non-stoichiometric SrCoO_(x) with rich oxygen-vacancy defects as channel materials for detecting extreme *** corresponding channel can provide effective oxygen-ion-migration sites for reversible transformation of OH-↔O_(2)-+H^(+)driven by electric *** resultant electrolyte-gated FET sensor exhibits a sensitive linear response to high concentrations of alkaline solution,1–20 ***,the sensor has the ability to directly indicate the pH values ranging from 14.0 to 17.0 in consideration of ion-activity coefficient *** work offers a great possibility for directly detecting base concentration as well as pH values in extreme alkaline solutions.

关键词： field-effect-transistor(FET) pH sensor extreme alkaline solution SrCoO_(x) oxygen-ion migration

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基于充电抑制膜的航天器不等量电位控制方法

安全与电磁兼容 2024年第1期 31-37页

作者：王思展王志浩刘宇明王晶虎冯娜程千钉韩炎晖北京卫星环境工程研究所北京东方计量测试研究所

航天器在空间环境中飞行时,其表面的不同介质材料表面与等离子体环境相互作用后形成的不等量充电电位达到放电阈值(107 V/m)后,将有可能发生静电放电(ESD)。充电抑制膜是一种基于不等量电位梯度场发射原理的防护材料,当其上下表面电位... 详细信息

航天器在空间环境中飞行时,其表面的不同介质材料表面与等离子体环境相互作用后形成的不等量充电电位达到放电阈值(107 V/m)后,将有可能发生静电放电(ESD)。充电抑制膜是一种基于不等量电位梯度场发射原理的防护材料,当其上下表面电位差达到发射阈值后,充电抑制膜将发射电子从而对航天器结构不等量电位起到减缓作用。文章介绍了真空条件下充电抑制膜场电流发射特性,分析了充电抑制膜场电子发射对航天器表面不等量电位的控制效果,为航天器表面电位控制及减缓提供方法和依据。

关键词：主动电位控制航天器表面充电静电放电不等量带电

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碳解硅微粉在商用车轮胎胎面胶中的应用

轮胎工业 2024年第7期44卷 413-417页

作者：薛彬彬王志浩陈建军李培生山东华盛橡胶有限公司山东广饶257300

研究碳解硅微粉在商用车轮胎胎面胶中的应用。结果表明:碳解硅微粉的主要成分为二氧化硅,其各项理化性能均满足企业标准要求;采用碳解硅微粉部分或全部替代白炭黑,胶料的硫化特性和加工性能变化不大,硫化胶的压缩永久变形减小,压缩生热... 详细信息

研究碳解硅微粉在商用车轮胎胎面胶中的应用。结果表明:碳解硅微粉的主要成分为二氧化硅,其各项理化性能均满足企业标准要求;采用碳解硅微粉部分或全部替代白炭黑,胶料的硫化特性和加工性能变化不大,硫化胶的压缩永久变形减小,压缩生热降低,抗切割性能提高;成品轮胎的充气外缘尺寸、耐久性能和强度均满足国家标准要求,且可降低生产成本。

关键词：碳解硅微粉白炭黑商用车轮胎胎面胶压缩生热抗切割性能成本

Structural optimization design of semi-rigid base asphalt pavement using modulus matching criterion and multi-indicator range analysis

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 131-159页

作者： zhihao Yang Linbing wang Dongwei Cao Yinghao Miao Hailu Yang China Airport Planning&Design Institute Co. Ltd.Beijing 101312China Department of Road and Urban Railway Engineering Beijing University of TechnologyBeijing 100124China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China School of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaAthensGA 30602USA China-Road Transportation Verification&Inspection Hi-Tech Co. Ltd.Beijing 100088China

Damage to semi-rigid base asphalt pavement is related to improper matching of the pavement structure *** study mainly focused on the modulus matching of structural layers and the development of a pavement structure optimization ***,the modulus loss of existing pavement structures was analysed,and a three-dimensional finite element model was established based on the existing ***,the influence of the modulus of each structural layer on the mechanical response indicators and fatigue life was *** on the results,a pavement structure design method using the smoothness of the stress-strain curve as the modulus matching criterion of the structural layers was *** it was found that a strain convex point was present and that the stress mutation between the structural layers was significant when the modulus matching of the pavement structure was ***,the evaluation indicators were divided into two groups,namely,mechanical indicators and fatigue life *** it was proposed an optimized pavement structure design method based on modulus matching and multi-indicator range ***,the optimal modulus combination of pavement structure was determined by this *** research systematically studied the influence of the modulus of each structural layer on the mechanical response and fatigue life of the pavement,and proposed the concept and specific executive criteria of modulus matching for the first ***,it also provided an effective optimization method for pavement structure design.

关键词： Stress-strain curve Modulus matching Structural optimization design Multi-indicator range analysis Fatigue life

Experimental study of the settling of twin spherical particles released side by side: The impact of particle size, fluid viscosity, initial spacing,and particle density

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International Journal of Sediment Research 2023年第1期38卷 83-96页

作者： Yang Xiao Jieqing Liu Pei Zhang Jian Zhou Dongfang Liang zhihao wang Taotao Zhang Saiyu Yuan Hongwu Tang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Yangtze Institute for Conservation and Development Hohai University College of Water Conservancy and Hydropower Engineering Hohai University Institute of Water Science and Technology Hohai University School of Engineering Westlake University Department of Engineering University of Cambridge

The settling of solid particles in a fluid is an important process that needs to be considered in many fields of research. For example, the interactions among particles and between particles and the surrounding fluid are important topics in studying suspended sediment transport and water clarification. In this paper, the settling processes and interactions of twin spherical particles released side by side were experimentally studied. The Reynolds number varied in the range of 1-300, which is within the transition zone. Particle Tracking Velocimetry(PTV) and Particle Image Velocimetry(PIV) were utilized to capture the settlement trajectory, and provide insight into the flow fields around the particles. The influences of particle size, fluid viscosity, initial spacing, and particle density on the settling process were systematically investigated. The experimental results reveal that the initial spacing between the twin particles(l0*) and the Reynolds number(Re) are the two most important factors affecting particle settling. The interaction between particles comprises only repulsion when the initial spacing is small, while the density of particles has little effect on the final settling state when the initial spacing is not very small. The flow fields around different particles are similar for the same Re, leading to similar final settlement behaviors, except for the case of l0* = 0, when the influence of particle rotation cannot be ignored. Except for the case of l0* = 0, although the particle density has little effect on the final settling behavior, it affects the repulsive process during settling. The final repulsive distance between the twin particles is highly dependent on Re and l0*. Two critical Re values exist(～10 and ～100), where the repulsive distance is negatively correlated with Re when Re 100. However, the repulsive distance is always negatively correlated with l0*. These findings can improve understa

关键词： Particle settlement Repulsion of particles Particle tracking velocimetry (PTV) Particle image velocimetry (PIV) Particle density

Nano-alumina@cellulose-coated separators with the reinforcedconcrete-like structure for high-safety lithium-ion batteries

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Chinese Journal of Chemical Engineering 2024年第4期68卷 83-93页

作者： zhihao Yang Li Chen Jian Xue Miaomiao Su Fangdan Zhang Liangxin Ding Suqing wang Haihui wang Guangdong Provincial Key Lab of Green Chemical Product Technology School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China Beijing Key Laboratory of Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Separators play a critical role in the safety and performance of lithium-ion ***,commercial polyolefin separators are limited by their poor affinity with electrolytes and low melting *** this work,we constructed a reinforced-concrete-like structure by homogeneously dispersing nano-Al_(2)O_(3) and cellulose on the separators to improve their stability and *** this reinforcedconcrete-like structure,the cellulose is a reinforcing mesh,and the nano-Al_(2)O_(3) acts as concrete to support the *** constructing the reinforced-concrete-like structure,the separators exhibit good stability even at 200℃(thermal shrinkage of 0.3%),enhanced tensile strain(tensile stress of 133.4 MPa and tensile strains of 62%),and better electrolyte wettability(a contact angle of 6.5°).Combining these advantages,the cells with nano-Al_(2)O_(3)@cellulose-coated separators exhibit stable cycling performance and good rate ***,the construction of the reinforced-concretelike structure is a promising technology to promote the application of lithium-ion batteries in extreme environments.

关键词： Alumina Nanomaterials Lithium-ion batteries Membranes Cellulose Reinforced-concrete-like structure

Feasibility study of a large-scale tuned mass damper with eddy current damping mechanism

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 391-401页

作者： wang zhihao Chen Zhengqing wang Jianhui Wind Engineering Research Center Hunan UniversityChangsha 410082China School of Civil Engineering and Communication North China University of Water Resources and Electric PowerZhengzhou 450011China

Tuned mass dampers （TMDs） have been widely used in recent years to mitigate structural vibration. However, the damping mechanisms employed in the TMDs are mostly based on viscous dampers, which have several well-known disadvantages, such as oil leakage and difficult adjustment of damping ratio for an operating TMD. Alternatively, eddy current damping （ECD） that does not require any contact with the main structure is a potential solution. This paper discusses the design, analysis, manufacture and testing of a large-scale horizontal TMD based on ECD. First, the theoretical model of ECD is formulated, then one large-scale horizontal TMD using ECD is constructed, and finally performance tests of the TMD are conducted. The test results show that the proposed TMD has a very low intrinsic damping ratio, while the damping ratio due to ECD is the dominant damping source, which can be as large as 15% in a proper configuration. In addition, the damping ratios estimated with the theoretical model are roughly consistent with those identified from the test results, and the source of this error is investigated. Moreover, it is demonstrated that the damping ratio in the proposed TMD can be easily adjusted by varying the air gap between permanent magnets and conductive plates. In view of practical applications, possible improvements and feasibility considerations for the proposed TMD are then discussed. It is confirmed that the proposed TMD with ECD is reliable and feasible for use in structural vibration control.

关键词： tuned mass damper eddy current damping permanent magnets conductive plate modal damping ratio