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Light weight optimization of stratospheric airship envelope based on reliability analysis

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Chinese Journal of Aeronautics 2020年第10期33卷 2670-2678页

作者： Yunce ZHANG Yafei wang changguo wang National Key Laboratory of Science and Technology for National Defence on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China Center for Composite Materials Harbin Institute of TechnologyHarbin 150001China

A stratospheric airship is an essential flight vehicle in the aviation *** this paper,optimal design approach of stratospheric airships is developed to optimize envelope shape considering three failure modes and multidisciplinary analysis models,and could also reduce the mass of a stratospheric airship to be deployed at a specific *** on a theoretical analysis,three failure modes of airships including bending wrinkling failure,hoop tearing failure and bending kink failure,are given to describe and illustrate the failure mechanism of stratospheric *** results show that the location,length and size of the local uniform load and the large fineness ratio are easier to lead to bending wrinkling failure and bending kink *** small fineness ratio and the increasing differential pressure are more prone to cause hoop tearing failure for an airship *** failure probability is sensitive to the wind *** an optimization design,the reliability analysis is essential to be carried out based on the safety of the *** solution in this study can provide economical design recommendations.

关键词： Failure modes Mass optimization Optimal design Reliability analysis Stratospheric airship

Deployment of SMP Miura-ori sheet and its application:Aerodynamic drag and RCS reduction

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Chinese Journal of Aeronautics 2022年第8期35卷 121-131页

作者： Ji ZHANG changguo wang Lamei ZHANG National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China Center for Composite Materials and Structures Harbin Institute of TechnologyHarbin 150001China Department of Information Engineering Harbin Institute of TechnologyHarbin 150001China

Origami,such as Miura-ori,is the art of folding two-dimensional materials into complex,elaborate,and multifunctional three-dimensional *** this paper,SMP MO sheet are prepared,and the accuracy of deployable process is verified by *** folding and deployable process of SMP MO sheet is divided into 4 stages,and each stage is described in *** stiffness of smart deployable stage is characterized by an exponential decline at the beginning and a gradual decrease to 0,and this is similar to the theoretical shear equivalent modulus in the Y *** effects of various parameters on strain and stress are also *** purpose of studying these mechanical characteristics is to provide driving force reference in application;In terms of application,the flow field and electromagnetic characteristics of MO sheet in different directions are *** aerodynamic drag and RCS reduction of MO unit cell and graded MO sheet during the deployable process are *** the dihedral fold angle is about 45°,the RCS reduction and drag reduction characteristics of MO sheet are relatively optimal,which is most beneficial to morphing aircraft.

关键词： Aerodynamic characteristics Deployment Miura-Ori Morphing aircraft RCS reduction SMP sheet

Pressure-induced instability and its coupled aeroelasticity of inflated pillow

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Chinese Journal of Aeronautics 2022年第2期35卷 1-7页

作者： Ji ZHANG changguo wang Jiaming GUO Jiawei ZHANG National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China Special Environments Harbin Institute of TechnologyHarbin 150080China b Center for Composite Materials and StructuresHarbin Institute of TechnologyHarbin 150001China

A floating air weapon system(such as airborne floating mines)plays an important role in modern air defense *** paper focuses on aeroelastic characteristics of airborne floating mine named inflated ***,the dynamic deployable process of the pillow and characteristics of the local instability of the edge are studied,and the evolution mechanism of wrinkles and kinks is ***,in the cruising stage,the fluid-structural-thermal coupling analysis is performed on the pillow,and the aeroelastic characteristics are ***,the shapepreserving effect of the inflated pillow during the“negative pressure”slow landing stage is *** is found that when the wind velocity is higher,the pillow has a collapsed instability(surface extrusion and contact),and when the wind velocity is lower,snap-through instability ***,for the collapsed instability,a carbon fiber skeleton is added to discrete the large global collapsed fold into small local folds,thus achieving shape-preserving effect of *** snapthrough instability,the critical internal pressure and different shape evolution under different wind velocity are *** the analysis of the mechanical mechanism and control of the structural morphological evolution,it provides theoretical guidance for the application of the curved shell structure in floating air weapon system.

关键词： Aeroelastic analysis Fluid-structural-thermal coupling analysis Inflated pillow Kink Pressure-induced instability Wrinkle

Frequency reconfigurable antenna actuated by inflated triangular structure:Design and analysis

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Chinese Journal of Aeronautics 2023年第5期36卷 280-285页

作者： Jiaming GUO Xinghan QIU Jiawei ZHANG Lamei ZHANG changguo wang School of Astronautics Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin 150001China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China

This paper proposes a frequency reconfigurable triangular antenna actuated by an inflated triangular *** open path antenna is transformed from an open type to a closed structure by *** structures are easy to manufacture by fusing 2 inextensible membranes together along a defined pattern of ***,the prediction of their deployed shape remains a *** solve the pattern changed problem,guided by geometric analyses and local buckle characteristics,the inflated triangular structure has been designed and verified by experiment and *** the process of transformation of the antenna,the resonant frequency of the antenna is changed because this frequency is determined by the conformational *** resonant frequency changes from GHz to kHz when the design of initial structure sizes is from millimeter to *** measured peak gains,the frequency,and the radiation direction are also reconfigurable by the initial ***,the reconfigurable resonator array is presented,which is coupled to electric fields to absorb all incident *** this work,the changed pattern design by inflating is applied to the antenna design,and its frequency reconfigurability is *** the electricity performance analysis of the reconfigurable antenna,precise manufacturing will be possible and provide guidance for manufacturing frequency reconfigurable antennas.

关键词： Free kink design Frequency Reconfigurable Antenna(FRA) Inflated Return losses Thin film

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阴茎头血管瘤1例报告

中华泌尿外科杂志 2024年第3期45卷 229-230页

作者：刘朝阳张正果王丛巍王昌国朱建华贾占奎杨锦建郑州大学第一附属医院泌尿外科郑州450052

阴茎头血管瘤临床罕见,本文报道1例。患者16岁,因发现阴茎头多发肿物2年余入院。查体:阴茎头3、9、12点方向沿冠状沟分布可见3处血管团样肿物,较大者约10mm×5mm,呈蓝紫色,质软、无痛。超声检查提示阴茎头血管瘤,行手术切除治疗。术后... 详细信息

阴茎头血管瘤临床罕见,本文报道1例。患者16岁,因发现阴茎头多发肿物2年余入院。查体:阴茎头3、9、12点方向沿冠状沟分布可见3处血管团样肿物,较大者约10mm×5mm,呈蓝紫色,质软、无痛。超声检查提示阴茎头血管瘤,行手术切除治疗。术后病理诊断为阴茎头血管瘤。术后随访3个月,伤口愈合良好,无复发,阴茎头外形无明显畸形。

关键词：阴茎疾病血管瘤手术

Synthesis of ZSM-5@ Ordered Mesoporous Silica Composites by Dodecylamine Surfactant

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Journal of Wuhan University of Technology(Materials Science) 2014年第6期29卷 1124-1128页

作者：马扩彦俞海军 FENG Guanglin wang changguo 戴亚 Harmful Components and Tar Reduction in Cigarette Sichuan Key Laboratory Technical Research Center Chuanyu Branch of China Tobacco Corporation

The core-shell structures of ZSM-5 coated with mesoporous silica were synthesized by means of dodecylamine（DDA） surfactant. The results show that the mesoporous silica shells are coated on ZSM-5 cores and result in the formation of hierarchical porous structures. The thickness of the coating shell can be controlled by changing the adding amount of TEOS. The core-shell composites with the thickness of 35 nm possess high surface areas（about 528 m2·g-1）, large pores（about 3.5 nm in diameter） on the silica shells. The composite molecular sieves display higher adsorption capacity for benzene（140.2 mg·g-1） and butyraldehyde（213.7 mg·g-1） than that of pristine ZSM-5 for benzene（99.2 mg·g-1） and butyraldehyde（134.7 mg·g-1）. The composite molecular sieves show a wide application foreground for harmful gas adsorbent for environmental protection.

关键词： core-shell zeolite adsorption dodecylamine butyraldehyde benzene

A novel inflatable rings supported design and buoyancy-weight balance deformation analysis of stratosphere airships

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Chinese Journal of Aeronautics 2022年第1期35卷 340-347页

作者： Weinan GAO Ji ZHANG Teng MA Guochang LIN Yuanpeng LIU changguo wang Huifeng TAN Center for Composite Materials Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150080China

Owing to the unique advantages in flight altitude,dwelling time and wide coverage area,stratospheric airships provide permanent monitoring and surveillance for both civil and military *** we propose a semi-rigid stratosphere airship design with circumferential high-pressure inflatable rings and a longitudinal carbon fiber skeleton supported *** perform numerical simulations to analyze the deformation characteristics during the whole ascending and descending *** equivalent internal gradient pressure model of helium is established based on the capsule shape and buoyancy-weight equilibrium *** implicit dynamic method is used to deal with the large deformation of the airship capsule under a low negative pressure *** and load-bearing performance of the airship capsule,inflatable ring,skeleton,and suspension line are obtained under different working *** results show that the airship,supported with the inflatable rings and the suspension lines,effectively maintains the shape and ensures the stiffness during the ascending,dwelling,and descending stages,especially suffering from negative pressure.

关键词： Buoyancy-weight balance Large deformation Load-bearing performance Negative pressure Stratospheric airship

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长链烷基脲类消泡剂的合成及性能研究

化学反应工程与工艺 2024年第1期40卷 49-57页

作者：焦彦君汪昌国曹添陈小强南京工业大学江苏南京211816 江苏四新科技应用研究所股份有限公司江苏南京210028

开发无硅型消泡剂是未来消泡剂领域的发展方向之一。本工作将十八烷基异氰酸酯分别与油胺、1,6-己二胺和三(2-氨基乙基)胺反应合成了三种长链烷基脲,并以烷基脲为消泡活性物、矿物油为载体、Span-Tween为乳化剂制备了三种脲类消泡剂。... 详细信息

开发无硅型消泡剂是未来消泡剂领域的发展方向之一。本工作将十八烷基异氰酸酯分别与油胺、1,6-己二胺和三(2-氨基乙基)胺反应合成了三种长链烷基脲,并以烷基脲为消泡活性物、矿物油为载体、Span-Tween为乳化剂制备了三种脲类消泡剂。用核磁共振氢谱(1H NMR)和红外光谱(FT-IR)对产物进行结构表征。通过显微观察手段研究了疏水粒子在油基消泡剂中的消泡过程和机理,并通过单因素实验探究了各组成及用量对消泡剂性能的影响。结果表明:当选用低黏度白油,脲消泡活性物占消泡剂质量分数为4%,Span-Tween复合乳化剂亲水亲油平衡(HLB)值为8、用量占消泡剂质量分数为5%时,制得的脲类消泡剂在涂料应用中有着比同类市售产品更优异的消泡性能。

关键词：消泡剂脲消泡机理消泡性能涂料

Selective thermal emission and infrared camouflage based on layered media

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Chinese Journal of Aeronautics 2023年第3期36卷 212-219页

作者： Qingxiang JI Xueyan CHEN Vincent LAUDE Jun LIANG Guodong FANG changguo wang Rasoul ALAEE Muamer KADIC National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of TechnologyHarbin 150001China Institute FEMTO-ST CNRSUniversity Bourgogne Franche-Comte´Besanc¸on 25000France Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Department of Physics University of OttawaOttawaK1N 6N5Canada Institute of Theoretical Solid State Physics Karlsruhe Institute of TechnologyKarlsruhe D-76131Germany

Infrared camouflage based on artificial thermal metasurfaces has recently attracted significant *** eliminating thermal radiation differences between the object and the background,it is possible to hide a given object from infrared *** camouflage is an important element that increases the survivability of aircraft and missiles,by reducing target susceptibility to infrared guided ***,a simple and practicable design is theoretically presented based on a multilayer film for infrared stealth,with distinctive advantages of scalability,flexible fabrication,and structural *** multilayer medium consists of silicon substrate,carbon layer and zinc sulfide film,the optical properties of which are determined by transfer matrix *** locally changing the thickness of the coating film,the spatial tunability and continuity in thermal emission are demonstrated.A continuous change of emissive power is further obtained and consequently implemented to achieve thermal camouflage *** addition,other functionalities,like thermal illusion and thermal coding,are demonstrated by thickness-engineered multilayer films.

关键词： Heat transfer manipulation Infrared camouflage Multilayer media Selective thermal emission Thermal illusion Transfer matrix method