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Design of a 400 N and 12 mm Mechanical Air Gap High Temperature Superconducting Linear Synchronous Motor

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稀有金属材料与工程 2011年第S3期40卷 319-321页

作者： Yen Fei1,2,3, Li Jing1,2,3, Zheng Shijun1,2,3, Jiang Donghui1,2,3, Liu Lu1,2,3, Liu Wei1,2,3, Ma Guangtong1,2,3, Wang Jiasu1,3, Wang Suyu1,3 1 Applied Superconductivity laboratory, southwest jiaotong university, chengdu 61003., china 2 state key laboratory of traction power, southwest jiaotong university, chengdu 61003., china 3 National laboratory for Rail Transit, chengdu 61003., china SW jiaotong Univ Appl Superconduct Lab Chengdu 610031 Peoples R China SW jiaotong Univ State Key Lab Tract Power Chengdu 610031 Peoples R China Natl Lab Rail Transit Chengdu 610031 Peoples R China

The static thrust output on a superconducting coated conductor coil at different excitation and alternating current suspended above a three phase alternating current long-stator comprised of copper coils is presented. Excitation current up to 45 A was applied through the superconducting coil acting as the excitation system of the superconducting linear synchronous motor (SLSM), alternating current up to 9 A was applied to the armature and magnetic air gaps of 10 and 15 mm were investigated for four different cases; coreless, with an iron core or yoke and both a core and yoke. By scaling up and converting the studied superconducting single pancake racetrack coil into a double pancake coil and connecting four of such coils in series, an SLSM prototype capable of generating 400 N of thrust output and 1 kW of power output with a 12 mm mechanical air gap operating at 77 K is proposed.

关键词： high temperature superconductivity linear synchronous motor long stator motor superconducting coil force measurements

Analysis of the Effects of Slope Geometry on the Dynamic Response of a Near-field Mountain from the Wenchuan Earthquake

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Journal of Mountain Science 2010年第4期7卷 353-360页

作者： XIAO Shiguo FENG Wenkai ZHANG Jianjing Department of Geoteehnical Engineering Southwest Jiaotong University Chengdu 610031 China state key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Department of C-eoteehnical Engineering Southwest Jiaotong University Chengdu 610031 China

Fourier spectra and acceleration response spectra of near-field acceleration records of the 2008 Wenchuan Earthquake have been *** fundamental frequencies(or predominant periods) were ***,the natural frequencies of a range of slopes with different geometric characteristics,such as height,slope ratio,and pattern,were *** seismic responses of the slopes were compared,and the variability of seismic response with the above geometric elements was *** show that if slope height increases,and provided that other conditions are unchanged,the natural frequency of the first mode of a doublesurface slope will change as a power ***,natural frequencies will diminish(based on a parabolic function) as the slope angle becomes *** the surface pattern and the number of surfaces on a slope can have a great impact on the seismic response of the ***,within a certain range of slope heights or angles,either height or angle will also greatly influence the variability of the seismic *** results of this research will be helpful to understanding seismic dynamic response features and explaining the ways that slope stability can be affected by earthquakes.

关键词： Wenchuan Earthquake Slope Geometric features Dynamic response Naturalfrequency

3D thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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Science china(Technological Sciences) 2010年第8期53卷 2172-2182页

作者： ZHANG YuJun 1&ZHANG WeiQing 2 1 state key laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics, Chinese Academy of Sciences,Wuhan 430071,china 2School of Civil Engineering,southwest jiaotong university,chengdu 61003.,china 1. state key laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China2. School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

One kind of 3D coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1/9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

A constitutive model of frozen soil with damage and numerical simulation for the coupled problem

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 699-711页

作者： ZHU ZhiWu, NING JianGuo& MA Wei 1 School of Mechanics and Engineering, southwest jiaotong university, chengdu 61003., china 2 state key laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, china 3 key laboratory of Frozen Soil Engineering, CAREERI, CAS, Lanzhou 730000, china 1. School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Key Laboratory of Frozen Soil Engineering CAREERI CAS Lanzhou 730000 China

Based on the microcosmic mechanics of composite materials, an elastic constitutive model for frozen soil with damage is presented. For frozen sandy soil with a range of ice contents and under a range of temperature conditions, quantitative results determined by this constitutive model agree with practically measured stress-strain curves. After numerically simulating the coupled water, temperature and stress fields of channel frozen and frozen roadbed using a self-developed finite-element routine, more accurate and practical calculation results for the temperature field coupled with stress, displacement and strain fields are obtained; the results match predictions and tests undertaken by earlier researchers. Our results support the reliability of our routine for calculating interdependent physical quantities of frozen soil and for describing the relationships between them. Our program can offer necessary constraints for engineering design and construction in permafrost regions.

关键词： frozen soil microcosmic mechanics roadbed coupling stress field

Analysis on Dam-Breaking Mode of Tangjiashan Barrier Dam in Beichuan County

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Journal of Mountain Science 2011年第2期8卷 354-362页

作者： HU Xiewen LUO Gang LV Xiaoping HUANG Runqiu SHI Yubin Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Chengdu 610031 China state key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Aseismic Engineering Technology key laboratory of Sichuan Province Southwest Jiaotong UniversityChengdu 610031 China chengdu Hydroelectric Investigation and Design Institute China Hydropower Consulting Group Chengdu 610072 China

Tangjiashan landslide is a typical high-speed consequent landslide of medium-steep dip angle. This landslide triggered by earthquake took place in about semi-minute. The relative sliding displacement is 900 meters, so average sliding speed is about 30 meters per second. The longitudinal length of barrier dam which is formed by high-speed landslide along river is 803.4 meters; and maximum width crossing river is 611.8 meters. And its volume is estimated about 20.37 million steres. Through detailed geological investigation of the barrier dam, together with early geological information before earthquake, geological structures of the barrier dam and its stability of upstream and downstream slopes are studied when water level reaches different elevations in condition of continual after shocks with seismic intensity of 7 or 8 Richter scale. On this basis, dam-breaking mode of barrier dam is discussed deeply. Thereby, analytic results provide significant guidance and advices to front headquarters of Tangjiashan barrier dam, so that some proper engineering measures can be implemented and flood discharge can be carried out well.

关键词： Tangjiashan Barrier Dam High-speed landslide Blocking river Dam-breaking

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高速动力车车轴强度分析的工程方法

铁道学报 2002年第2期24卷 26-29页

作者：米彩盈李芾西南交通大学机车车辆研究所四川成都610031 西南交通大学牵引动力国家重点实验室四川成都610031

基于弹性力学理论 ,以车轴的受力状态和载荷分布为基础 ,建立车轴强度计算模型 ,导出车轴强度计算公式。给出车轴结构应力集中系数的计算方法和新型车轴制造材料的安全系数和许用应力的确定方法。与有限元法相比 ,方法简单 ,易于计算机... 详细信息

基于弹性力学理论 ,以车轴的受力状态和载荷分布为基础 ,建立车轴强度计算模型 ,导出车轴强度计算公式。给出车轴结构应力集中系数的计算方法和新型车轴制造材料的安全系数和许用应力的确定方法。与有限元法相比 ,方法简单 ,易于计算机计算。与试验结果对比 ,二者的最大相对误差小于 10 %。

关键词：高速动力车车轴强度计算工程方法强度试验

Analysis of vibration reduction characteristics and applicability of steel-spring floating-slab track

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Journal of Modern Transportation 2011年第4期19卷 215-222页

作者： Wanming ZHAI Peng XU Kai WEI traction power state key laboratory Southwest Jiaotong University Chengdu 610031 China

A coupled dynamics computation model for metro vehicles, along with a steel-spring floating-slab track, is developed based on the theory of vehicle-track coupled dynamics. Using the developed model, the influences of the thickness, length and mass of floating-slab, spring rate and its arrangement space, running speed, etc. on the time and frequency domain characteristics of steel-spring fulcrum force are analyzed. The applicability of steel-spring floatingslab track is discussed through two integrated example cases of metro and buildings possessing distinct natural vibra- tion characteristics. It is concluded that, it is quite significant, in the optimization modular design of the parameters of steel-spring floating-slab track, to take the matching relationship of both the amplitude-frequency characteristics of steel-spring fulcrum force and natural vibration characteristics of integrated structures into comprehensive consideration. In this way the expensive steel-spring floating-slab track can be economically and efficiently utilized according to the site condition, and at the same time, the economic losses and bad social impact resulted from the resonance during usage of steel-spring floating-slab track can be avoided.

关键词： integrated structures natural vibration characteristics subway vibration steel-spring floating-slab track steel-spring fulcrum force frequency spectrum analysis

An improved algorithm for fluid-structure interaction of high-speed trains under crosswind

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Journal of Modern Transportation 2011年第2期19卷 75-81页

作者： Tian LI Jiye ZHANG Weihua ZHANG traction power state key laboratory Southwest Jiaotong University Chengdu 610031 China

Based on the train-track coupling dynamics and high-speed train aerodynamics, this paper deals with an improved algorithm for fluid-structure interaction of high-speed trains. In the algorithm, the data communication between fluid solver and structure solver is avoided by inserting the program of train-track coupling dynamics into fluid dynamics program, and the relaxation factor concerning the load boundary of the fluid-structure interface is introduced to improve the fluctuation and convergence of aerodynamic forces. With this method, the fluid-structure dynamics of a highspeed train are simulated under the condition that the velocity of crosswind is 13.8 m/s and the train speed is 350 km/h. When the relaxation factor equals 0.5, the fluctuation of aerodynamic forces is lower and its convergence is faster than in other cases. The side force and lateral displacement of the head train are compared between off-line simulation and co-simulation. Simulation results show that the fluid-structure interaction has a significant influence on the aerodynam- ics and attitude of the head train under crosswind conditions. In addition, the security indexes of the head train worsen after the fluid-structure interaction calculation. Therefore, the fluid-structure interaction calculation is necessary for high-speed trains.

关键词： high-speed train fluid-structure interaction crosswind aerodynamics relaxation factor

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铁路有砟轨道下沉破坏研究进展

铁道学报 2008年第5期30卷 97-104页

作者：高建敏翟婉明西南交通大学牵引动力国家重点实验室四川成都610031

轨道累积下沉是轨道不平顺发生、发展的根源,是各种线路病害的动力源,由此形成以轨道下沉研究为主体的轨道下沉破坏理论。轨道下沉破坏研究是轨道管理基础研究工作中的重要内容。国内外对有关轨道累积下沉特性及下沉影响因素等问题给予... 详细信息

轨道累积下沉是轨道不平顺发生、发展的根源,是各种线路病害的动力源,由此形成以轨道下沉研究为主体的轨道下沉破坏理论。轨道下沉破坏研究是轨道管理基础研究工作中的重要内容。国内外对有关轨道累积下沉特性及下沉影响因素等问题给予高度重视,曾进行广泛研究。本文综述国内外关于轨道下沉破坏的研究历史与现状,主要包括轨道下沉试验研究、轨道下沉破坏仿真计算研究和轨道下沉与轨面高低不平顺发展关系研究。通过总结和分析,明确国内外研究状况和发展动向,对比国内轨道管理基础研究状况,指出我国为适应现代轨道养护维修管理需要在轨道下沉破坏方面进一步重点研究的问题。

关键词：铁路轨道有砟轨道下沉破坏研究进展