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Energy Geoscience 2024年第3期5卷 351-361页

作者： Chao Zhang Pinjia duan Yuke Cheng na Chen Huan Huang Feng Xiong Shaoqun Dong CNOOC Gas&Power Group Ltd. Beijing100028China School of Civil engineering and Architecture Hubei University of TechnologyWuhan430068China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China college of Science China University of Petroleum(Beijing)Beijing102249China

Underground liquified natural gas(LNG)storage is essential in guaranteeing national energy strategic reserves,and its construction is being *** stability of surrounding rock of underground LNG storage caverns under stress-low temperature coupling effect is the key factor determining the feasibility of LNG ***,a mathematical model used for controlling the stress-low temperature coupling and the processes of rock damage evolution is given,followed by a 2-D numerical execution process of the mathematical model mentioned above described based on Comsol Multiphysics and Matlab ***,a series of 2-D simulations are performed to study the influence of LNG storage cavern layout,burial depth,temperature and internal pressure on the stability of surrounding rocks of these underground storage *** results indicate that all the factors mentioned above affect the evolution of deformation and plastic zone of surrounding *** research results contribute to the engineering design of underground LNG storage caverns.

关键词： Underground LNG storage Thermo-mechanical(TM)coupling Stability of surrounding rock Low temperature Comsol Multiphysics

Comparison of electrochemical behaviors of Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe and Ti-6Al-4V titanium alloys in naNO_(3) solution

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 750-763页

作者： Jia Liu Shuanglu duan Xiaokang Yue Ningsong Qu college of mechanical and Electrical engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion *** machining(ECM)is an efficient and low-cost technology for manufacturing theβ-CEZ *** ECM,the machining parameter selection and tool design are based on the electrochemical dissolution behavior of the *** this study,the electrochemical dissolution behaviors of theβ-CEZ and Ti-6Al-4V(TC4)alloys in naNO3solution are *** open circuit potential(OCP),Tafel polarization,potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),and current efficiency curves of theβ-CEZ and TC4 alloys are *** results show that,compared to the TC4 alloy,the passivation film structure is denser and the charge transfer resistance in the dissolution process is greater for theβ-CEZ ***,the dissolved surface morphology of the two titanium-based alloys under different current densities are *** low current densities,theβ-CEZ alloy surface comprises dissolution pits and dissolved products,while the TC4 alloy surface comprises a porous honeycomb *** high current densities,the surface waviness of both the alloys improves and the TC4 alloy surface is flatter and smoother than theβ-CEZ alloy ***,the electrochemical dissolution models ofβ-CEZ and TC4 alloys are proposed.

关键词： electrochemical machining dissolution behavior β-CEZ titanium alloy polarization curve current efficiency

Study on Segmented Reflector Lamp Design Based on Error Analysis

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厦门大学学报（自然科学版） 2002年第S1期41卷 143-144页

作者： LIU Hong, YUAN Ju-long (college of mechanical & electronical engineering, Zhejiang University of Technology, Hangzhou 310014, china)

This paper discusses the basic principle and design m ethod for light distribution of car lamp, introduces an important development: h igh efficient and flexible car lamp with reflecting light distribution-segmente d reflector (multi-patch) car lamp, and puts out a design method for segmented reflector based on error analysis. Unlike classical car lamp with refractive lig ht distribution, the method of reflecting light distribution gives car lamp desi gn more flexibility. In the case of guarantying the lightness of car lamp and sa tisfying the standard demand for the light distribution, the design of the exter ior of the car lamp has more freedom. The high gradient of car lamp is more suit able for the demand of streamline of the car exterior. The shape of segmented re flector obtained by theory calculating of car lamp reflecting light distribution is only an ideal shape, which usually has considerable differences with the fin al shape and will influences light distribution. There exist difference between the calculated reflector and manufactured reflector. Owing to light reflecting c haracter, the small diversification of the reflector will reduce the big diver sification of the light distribution shape on light distribution screen in 25 -meter place, so light distribution quality can’t be ensured. To ensure the re flector by light distribution calculation accordance to reflector by practical m anufacture, the error effect of surface shape must be reasonably considered name ly the error effect of manufacture tache. The paper establishes error-analyzing model for segmented reflector according to the analysis of error of making proc ess for segmented reflector. Based on this error-analyzing model and by use of the analyzing software developed for segmented reflector light distribution, it could reasonably consider reflector errors made by manufacturing, such as reflec tor surface spray-painting and plating aluminum, which could give out shapes of reflector patches fo

关键词： car lamp design light distribution segmented surface reflector

Transient flameout process of boron-magnesium agglomerates during combustion in oxygen-rich atmospheres

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Particuology 2024年第5期88卷 290-301页

作者： Lian duan Zhixun Xia Yunchao Feng Binbin Chen Likun Ma Jianxin Hu college of Aerospace Science and engineering National University of Defense TechnologyChangsha 410073China School of mechanical engineering and Mechanics Xiangtan UniversityXiangtan 411105China

In this study,boron–magnesium agglomerates with varying mass ratios were prepared by drying a micron-sized boron–magnesium mixed suspension,and the combustion process of these agglomerates under different oxygen-rich concentrations were investigated using a laser ignition *** test results showed that when the mass fraction of magnesium powder in boron-magnesium agglomerates exceeded a certain threshold(between 2%and 5%),flame extinction and reignition occurred after a significant reduction in the agglomerate volume during *** process is referred to as the transient flameout process,which is affected by the magnesium content of the agglomerate and the oxygen concentration in the ambient *** increase in the magnesium content or oxygen concentration makes this phenomenon more *** weakening of the flame intensity,a dark film gradually covered the particle surfaces.X-ray diffraction and elemental analyses of the cross-section and outer surface of the condensed combustion product suggested that the dark film is primarily composed of Mg-B-O ternary *** film prevents direct contact between boron and oxygen,thereby inhibiting surface and gas-phase reactions and leading to the occurrence of the transient flameout phenomenon.

关键词： Agglomerated particle Boron–magnesium fuel Boron combustion Transient flameout process Solid fuel ramjet

Visualization Simulations for Cold Press Die

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厦门大学学报（自然科学版） 2002年第S1期41卷 31-32页

作者： LIU Hong, YUAN Ju-long, JIN Jie (college of mechanical & electronical engineering, Zhejiang University of Technology, Hangzhou 310014, china)

Pressing process is a manufacturing method that obtained work piece with certain dimension, shape and capability through die forcing roughcast to produce plastic deformation or separate. This paper focuses on the key problems of visualization simulation in pressing die. The final aim is that numerical simulation system can simulate the process of processing forming technique, which can supply some necessary and accurate key parameters for die design. The detail description of mechanical characteristic and key technique of sheet forming technique is discussed. Pressing forming method is one of the most important forming techniques of metal forming, which has special mechanical characteristics. The character of sheet pressing forming is that the deformation of thickness direction is very small in contrast to other directions. The deformation mode of sheet forming mainly has the following kinds: bi-directional stretch, plane stress, stretches, depths extend, bending and counter-bending. The essence of press forming is the transferring course that the transferring region of rough comes to deformation by outside force, which is main researching principle in forming and the transferring field. The analysis of pressing forming course, disclose the feature of stress-strain and their changing rule, then pressing process and forming parameters could be obtained. So the states of force and deformation of transferring region is key to determine character about the varieties of pressing transferring. The paper analyzes these factors, which may influence forming precision in pressing process. In traditional methods, some key parameter such as spring-back, bending radius for die design are calculated by experience formula or select from data table. The paper brings forward the calculation methods of key parameter in the case of drawing finite element method and numerical simulation into pressing die design. In order to calculate the value of key parameters based on data supplied b

关键词： cold press die visualization simulating

Near-zero-adhesion-enabled intact wafer-scale resist-transfer printing for high-fidelity nanofabrication on arbitrary substrates

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International Journal of Extreme Manufacturing 2024年第1期6卷 313-326页

作者： Zhiwen Shu Bo Feng Peng Liu Lei Chen Huikang Liang Yiqin Chen Jianwu Yu Huigao duan college of mechanical and Vehicle engineering National Engineering Research Centre for High Efficiency GrindingHunan UniversityChangsha 410082People’s Republic of China Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300People’s Republic of China School of mechanical engineering Hunan University of Science and TechnologyXiangtan 411201People’s Republic of China Shenzhen Research Institute Hunan UniversityShenzhen 518000People’s Republic of China

There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates,so as to meet the fast-growing need for broad applications in nanoelectronics,nanophotonics,and fexible *** direct-lithography methods are difficult to use on fexible,nonplanar,and biocompatible ***,this fabrication is usually accomplished by nanotransfer ***,large-scale integration of multiscale nanostructures with unconventional substrates remains challenging because fabrication yields and quality are often limited by the resolution,uniformity,adhesivity,and integrity of the nanostructures formed by direct ***,we proposed a resist-based transfer strategy enabled by near-zero adhesion,which was achieved by molecular modification to attain a critical surface energy *** approach enabled the intact transfer of wafer-scale,ultrathin-resist nanofilms onto arbitrary substrates with mitigated cracking and wrinkling,thereby facilitating the in situ fabrication of nanostructures for functional *** this approach,fabrication of three-dimensional-stacked multilayer structures with enhanced functionalities,nanoplasmonic structures with~10 nm resolution,and MoS2-based devices with excellent performance was demonstrated on specific *** results collectively demonstrated the high stability,reliability,and throughput of our strategy for optical and electronic device applications.

关键词： resist-based transfer printing near-zero adhesion critical surface energy wafer-scale nanofabrication in situ fabrication optoelectronic devices

Research on Anti-Fluctuation Control of Winding Tension System Based on Feedforward Compensation

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Computer Modeling in engineering & Sciences 2024年第5期139卷 1239-1261页

作者： Yujie duan Jianguo Liang Jianglin Liu Haifeng Gao Yinhui Li Jinzhu Zhang Xinyu Wen college of mechanical and Vehicle engineering Taiyuan University of TechnologyTaiyuan030024China college of Electronic Information and Optical engineering Taiyuan University of TechnologyTaiyuan030024China School of Electronic Information engineering Taiyuan University of Science and TechnologyTaiyuan030000China

In the fiber winding process,strong disturbance,uncertainty,strong coupling,and fiber friction complicate the winding constant tension *** order to effectively reduce the influence of these problems on the tension output,this paper proposed a tension fluctuation rejection strategy based on feedforward *** addition to the bias harmonic curve of the unknown state,the tension fluctuation also contains the influence of bounded noise.A tension fluctuation observer(TFO)is designed to cancel the uncertain periodic signal,in which the frequency generator is used to estimate the critical parameter ***,the fluctuation signal is reconstructed by a third-order auxiliary *** estimated signal feedforward compensates for the actual tension ***,a time-varying parameters fractional-order PID controller(TPFOPID)is realized to attenuate the bounded noise in the ***,TPFOPID is enhanced by TFO and applied to control a tension control system considering multi-source *** stability of the method is analyzed by using the Lyapunov ***,numerical simulations verify that the proposed scheme improves the tracking ability and robustness of the system in response to tension fluctuations.

关键词： Constant tension control anti-fluctuation strategy tension fluctuation observer time-varying parameters fractional-order PID controller feedforward compensate

Analysis of Dynamic Response of Explosive Disposal Robot to Rough Road Excitation

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武汉理工大学学报 2006年第S2期28卷 513-516页

作者： MO Haijun HUANG Ping HU Qingchun duan Fuhai (college of mechanical engineering,South china University of Technology,guangzhou 510640,china college of mechanical engineering South China University of TechnologyGuangzhou 510640China

When the explosive disposal robot traveling over a rough road,it will shake up and down,and generates dynamic ***,the jolt of the explosive disposal robot will result in oscillation and large inertia forces of the explosive,and will effect the stability of the grasped explosive,even cause the explosive slipping from the claw and falling to the ground,which seriously threats the saJety of the robot and around environment.A tracked explosive dispasal robot has been developed at South Chi- na University of *** paper takes the explosive disposal robot and the grasped explosive as study *** fo- cuses on the response analysis of the grasped explosive when the robot traveling over a rough *** the vibration character- istic of the explosive and the effects of the robot moving speeds on the stability of the *** dynamic response of the explosive is obtained by simulation,the results show that the velocity of the robot is a sensitivity influence factor on the oscillation of grasped explosive.

关键词： explosive disposal robot explosive rough road dynamic response

Study on the mechanism and law of temperature,humidity and moisture content on the mechanical properties of molded fiber products

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Journal of Bioresources and Bioproducts 2024年第3期9卷 351-368页

作者： Zhiqiang Fu Tong Zhao Hu Wang Jingyi Wei Haozhe Liu Liying duan Yan Wang Ruixiang Yan School of Light Industry Science and engineering Tianjin University of Science and TechnologyTianjin 300457China Department of Transportation and Vehicle engineering Tangshan UniversityTangshan 063000HebeiChina college of mechanical engineering Tianjin University of Science and TechnologyTianjin 300457China

The change of temperature, humidity and moisture content (MC) will lead to the change of mechanical properties of molded fiber products (MFP). However, it is difficult to decouple the effects of temperature, humidity and MC on the mechanical properties of MFP, and predict the mechanical properties of MFP during the use. In this study, the laws and mechanism of mechanical properties of MFP with ambient temperature, humidity and MC were studied. The results showed that the direct effect of temperature (20−70 °C) on mechanical properties of MFP was insignificant, and the mechanical properties of MFP were mainly changed by MC. The MC was related to ambient temperature and humidity, and the relationship between the three could be described by the modified guggenheim-Anderson-de Boer (GAB) model (20−70 °C and 30 %–90 % relative humidity). With the increase of MC, the elastic modulus and fracture strain was increased and decreased linearly, the yield strength and failure strength were presented GaussAmp laws, and the failure strain was presented asymptotic regressed distribution law. Two fracture modes of MFP, brittle fracture and ductile fracture, were revealed by the scanning electron microscopy of the mesoscopic fiber structure of sugarcane bagasse molded fiber products. The mathematical models and the changes of fiber structure were verified by wheat straw molded fiber products and waste paper molded fiber products. This study was contributed to understand the effects and mechanism of the change of temperature, humidity and MC on the mechanical properties of MFP.

关键词： Temperature Relative humidity Moisture content Molded fiber products mechanical properties