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1.  Electromagnetic and Stress Analyses of the ITER Equatorial Thermal Shield  
   雷明准  宋云涛  王松可  汪献伟《等离子体科学和技术》,2013年第15卷第8期
   The ITER equatorial thermal shield is located inside the cryostat and outside the vacuum vessel, and its purpose is to provide a thermal shield from hot components to the superconducting magnets. Electromagnetic analysis of the equatorial thermal shield was performed using the ANSYS code, because electromagnetic load was one of the main loads. The 40 sector finite element model was established including the vacuum vessel, equatorial thermal shield, and superconducting magnets. The main purpose of this analysis was to investigate the eddy current and electromagnetic force in the equatorial thermal shield during plasma disruption. Stress analysis was implemented under the electromagnetic load. The results show that the equatorial thermal shield can accommodate the calculated electromagnetic loads.    

2.  Elasto-plastic analysis of crack in metallic foams  
   解凌云  孙俊君  孙竹凤  范天佑《北京理工大学学报(英文版)》,2012年第21卷第3期
   To determine the solutions of the well-known problem of a finite width strip with single edge crack,some results on elasto-plastic fracture analysis for metallic foams are reported.Meanwhile,in order to discuss and put an insight into the nonlinear fracture analysis,the Dugdale model for plastic deformation of this configuration for metallic foams is recommended and solved.Combining the asymptotic solution with the Dugdale model and elastic solution,the stress field in the plastic zone and the size of the plastic zone are expressed as analytical forms.Based on Williams expansion method,the estimate of the scale factor is also completed and analyzed.In view of these analytical solutions,the results show the scale factor is a useful parameter for the fracture theory of metallic foams.    

3.  FEM SIMULATION FOR LASER FORMING PROCESSING  被引次数:1
   L.O.Li Y.B.Chen X.Y.Wang S.Y.Lin《金属学报(英文版)》,2004年第17卷第3期
   Laser forming involves heating sheet metal workpiece along a certain path with a defocused laser beam directed irradiate to the surface. During laser forming, a transient temperature fields is caused by the irradiation and travelling of a laser beam. Consequently, thermal expansion and contraction take place, and allows the thermalmechanical forming of complex shapes. This is a new manufacturing technique that forming metal sheet only by thermal stress. Therefore, the analysis of temperature fields and stress fields are very useful for studying the forming mechanism and controlling the accuracy of laser forming. The non-liner finite element solver, MARC, is employed to solve the thermal-mechanical analysis. Using this model, the stress and strain distribution of pure aluminum plate with different thickness are analyzed. The influence of scanning speed on temperature fields and plastic strain of metal sheet under the condition of constant line energy are also presented. Numerical results agree well with the exT~erimental results.    

4.  THERMAL STRESSES RELAXATION DESIGN OF Ni/NiFe2O4 SYSTEM FUNCTIONALLY GRADED CERMET INERT ANODE  
   J. Li Q.S. Zhang Y.Q. Lai S.L. Ye Y.X. Liu《金属学报(英文版)》,2005年第18卷第5期
   The thermal stresses relaxation of Ni/NiFe2O4 system functionally graded cermet inert anode for aluminum electrolysis was optimally designed. The transient thermal stresses of the inert anode under complex boundary condition during high-temp (955℃) electrolysis were calculated using the finite-element software ANSYS, the influence of different parameters on the distribution of the thermal stresses were analyzed. The results showed that, during the process of thermal shock, the thermal hoop tensile stress on the surface of the anode is very large, which is possibly the major cause of anode crack; when the radius of the anode is between 0.05-0.15m, a range that can be realized by recent manufacturing technology, the optimum composition distribution exponent p is 0.25; The hoop tensile stresses reduce with the decrease of anode scale and also decrease with the decrease of the convection coefficient between the electrolyte and the anode.    

5.  Transient Evolution of Inter Vessel Gap Pressure Due to Relative Thermal Expansion Between Two Vessels  
   K.Natesan  P.Selvaraj  P.Chellapandi  S.C.Chetal《热科学学报(英文版)》,2002年第11卷第3期
   In a typical liquid metal cooled fast breeder reactor (LMFBR), a cylindrical sodium filled main vessel, which carries the internals such as reactor core, pumps, intermediate heat exchangers etc. is surrounded by another vessel called safety vessel. The inter vessel gap is filled with nitrogen. During a thermal transient in the pool sodium, because of the relative delay involved in the thermal diffusion between MV and SV, they are subjected to relative thermal expansion or contraction between them. This in turn results in pressurisation and depressurisation of inter vessel gap nitrogen respectively. In order to obtain the external pressurization for the buckling design of MV, transient thermal models for obtaining the evolutions of MV, SV and inter gap nitrogen temperatures and hence their relative thermal expansion and inter vessel gap pressure have been developed. This paper gives the details of the mathematical model, assumptions made in the calculation and the results of the analysis.    

6.  An Analytic Solution of One-dimensional Steady-state Pennes' Bioheat Transfer Equation in Cylindrical Coordinates  被引次数:1
   Kai YUE Xinxin ZHANG Fan YU School of Mechanical Engineering  University of Science and Technology Beijing  Beijing 100083  China《热科学学报(英文版)》,2004年第3期
   Based on the Pennes' bioheat transfer equation, a simplified one-dimensional bioheat transfer model of the cylindrical living tissues in the steady state has been set up for application in limb and whole body heat transfer studies, and by using the Bessel's equation, its corresponding analytic solution has been derived in this paper. With the obtained analytic solution, the effects of the thermal conductivity, the blood perfusion, the metabolic heat generation, and the coefficient of heat transfer on the temperature distribution in living tissues are analyzed. The results show that the derived analytic solution is useful to easily and accurately study the thermal behavior of the biological system, and can be extended to such applications as parameter measurement, temperature field reconstruction and clinical treatment.    

7.  Verification of Numerical Modeling in 2-D Wave Propagation in Rock  被引次数:2
   LEI Wei-dong HEFNY Ashraf TENG Jun ZHAO Jian SONG Hong-wei《中国矿业大学学报(英文版)》,2005年第15卷第4期
   Compressional harmonic wave propagation from a cylindrical tunnel or borehole in an intact rock is the basis for investigation of the practical explosion waves in a fractured rock mass. The amplitudes of the radial stress wave obtained from the universal distinct element code (UDEC) were compared with the analytical solutions for two cases with different conditions. Good agreements between the UDEC results and the analytical solutions have been achieved. It indicates that UDEC can model 2-D dynamic problems at a high degree of accuracy.    

8.  Thermal stress and fracture temperature prediction for flexible pavement  
   钟阳  耿立涛《哈尔滨工业大学学报(英文版)》,2010年第17卷第6期
   Analytical solutions of thermal stresses in multilayered elastic system whose materials characteristics are dependent on temperature are derived by a transfer matrix and integral transformation method.The resulting formulation is used to calculate thermal stresses in the low temperature cracking problem of asphalt pavement.Numerical simulations and analyses are performed using different structural combinations and material characteristics of base course.And fracture temperatures are predicted for a given flexible pavement constructed with three types of asphalt mixtures based on the calculated results and experimental data.This approach serves as a better model for real pavement structure as it takes into account the relationships between the material characteristics and temperature in the pavement system.    

9.  Failure pressure calculation of fracturing well based on fluid-structure interaction  
   Jinzhou Zhao  Lan Ren  Min Li  Yongming Li State《岩石力学与岩土工程学报(英文版)》,2011年第Z1期
   Failure pressure is a key parameter in reservoir hydrofracturing operation. Existing analytical methods for calculating the failure pressure are based on the assumption that borehole fluid is under two extreme conditions: non-infiltration or complete infiltration. The assumption is not suitable for the actual infiltration process, and this will cause a great error in practical calculation. It shows that during the injection process, the dynamic variation in effective stress-dependent permeability has an influence on the infiltration, and the influence also brings about calculation errors. Based on the fluid-structure interaction and finite element method (FEM), considering partial infiltration during injection process, a numerical model for calculating rock failure pressure is established. According to the analysis of permeability test results and response-surface method, a new variation rule of rock permeability with the change of effective stress is presented, and the relationships among the permeability, confining pressure and pore pressure are proposed. There are some differences between the dynamic value of permeability-effective-stress coefficient observed herein and the one obtained by the classical theory. Combining with the numerical model and the dynamic permeability, a coupling method for calculating failure pressure is developed. Comparison of field data and calculated values obtained by various methods shows that accurate values can be obtained by the coupling method. The coupling method can be widely applied to the calculation of failure pressure of reservoirs and complex wells to achieve effective fracturing operation.    

10.  Flow stress of 2197 Al-Li alloy during hot compression deformation  
   魏修宇 郑子樵 付欣 陈秋妮《中国有色金属学会会刊》,2007年第17卷第A01期
   The flow stress behavior of 2197 Al-Li alloy during hot compression deformation was studied in the strain rate range from 0.01 to 10 s^-1 and the temperature range from 360 to 510℃ by isothermal compression test on a Gleeble-1500 thermal-mechanical simulator. The results show that the flow stress of 2197 Al-Li alloy decreases with the increase of deformation temperature and increases with the increase of strain rate. The peak flow stress during high temperature deformation can be represented by Z parameter in a hyperbolic sine function. The analytical expression of peak flow stress was fitted with the hot deformation activation energy of 260.6 kJ/mol.    

11.  Static and Dynamic Mechanical Analyses for the Vacuum Vessel of EAST Superconducting Tokamak Device  
   宋云涛 姚达毛 杜世俊 武松涛 翁佩德《等离子体科学和技术》,2006年第8卷第2期
   EAST (experimental advanced superconducting tokamak) is an advanced steadystate plasma physics experimental device, which is being constructed as the Chinese National Nuclear Fusion Research Project. During the plasma operation the vacuum vessel as one of the key component will withstand the electromagnetic force due to the plasma disruption, the Halo current and the toroidal field coil quench, the pressure of boride water and the thermal load due to 250℃ baking by pressurized nitrogen gas. In this paper a report of the static and dynamic mechanical analyses of the vacuum vessel is made. Firstly the applied loads on the vacuum vessel were given and the static stress distribution under the gravitational loads, the pressure loads, the electromagnetic loads and thermal loads were investigated. Then a series of primary dynamic, buckling and fatigue life analyses were performed to predict the structure's dynamic behavior. A seismic analysis was also conducted.    

12.  Gas Quenching during Age Hardening of the Aluminium Casting Alloy Al-7Si-0.3Mg  
   A.Rose O.Kessler F.Hoffmann H.W.Zoch《材料热处理学报》,2004年第25卷第5期
   For quenching of age hardenable aluminium alloys today predominantly aqueous quenching media are used,which can lead due to the Leidenfrost phenomenon to a non-uniform cooling of the parts and thus to thermal stresses.Particularly at thin-walled or complex shaped parts local plastic deformations can occur by the uneven thermal stresses. In relation to the conventional quenching procedures in aqueous media, gas quenching exhibits a number of technological,ecological and economical advantages. In comparison to liquid quenching media, gas does not change its phase during quenching. Moreover, the cleaning problem of the parts can be avoided. The quenching intensity can be adjusted by the variable parameters gas pressure and gas speed as well as the kind of gas and thus can be adapted to the requirements of the alloy. By the higher uniformity and the better reproducibility, gas quenching offers a high potential to reduce distortion. The goal of these investigations is to clarify, if the cooling rate during gas quenching is sufficient to obtain the specific required strength after age hardening of the alloy Al-7Si-0.3Mg. For this purpose different tests in high-pressure gas quenching facilities, gas nozzle fields and water quenching baths were performed.    

13.  Thermo-Mechanical Analysis of Water-Cooled Gun Barrel During Burst Firing  
   樊黎霞 胡志刚 赵建波《兵工学报(英文版)》,2006年第2卷第1期
   The thermo-mechanical stress and deformation of water-cooled gun barrel during burst firing are studied by finite element analysis (FEA). The problem is modeled in two steps: 1) A transient heat transfer analysis is first carried out in order to determine temperature evolution and to predict the residual temperatures during the burst firing event; 2) The thermo-mecha-nical stresses and deformation caused by both the residual temperature field and the gas pressure are then calculated. The results show that the residual temperature field tends to a steady state with the increasing of rounds. The residual temperature field has much effect on the gun barrel stress and deformation, especially on the assembly area between barrel and water jacket. The gage between the barrel and water jacket is the critical factor to the thermo- mechanical stress and deformation. The results of this analysis will be very useful to develop the new strength design theory of the liquid-cooled gun barrel.    

14.  Solution of an Inverse Problem of Heat Conduction of 45 Steel with Martensite Phase Transformation in High Pressure during Gas Quenching  被引次数:4
   HemingCHENG TianchunHE 等《材料科学技术学报》,2002年第18卷第4期
   In order to simulate thermal strains,thermal stresses,residual stresses and microstructure of the steel during gas quenching by means of the numerical method,it is necessary to obtain an accurate boundary condition of temperature field.The surface heat transfer coefficient is a key parameter.The explicit finite difference method,nonlinear estimation method and the experimental relation between temperature and time during gas quenching have been used to solve the inverse problem of heat conduction.The relationship between surface temperature and surface heat transfer coefficient of a cylinder has been given.The nonlinear surface heat transfer coefficients include the coupled effects between martensitic phase transformation and temperature.    

15.  Numerical Simulation for Roadways in Swelling Rock Under Coupling Function of Water and Ground Pressure  被引次数:1
   缪协兴  卢爱红  茅献彪  张东升《中国矿业大学学报(英文版)》,2002年第12卷第2期
   According to the analogical reiation in the governing differential equations of the humidity stress field theory and the temperature sttress field theory, the problem of solving the humidity stress field was trarsformed into that of .solving the temperature stress field by the change of parameters. As a result, the problem of roadways in swelling rock under the coupling function of water and ground pressure can be solved by the analytical module of temperature stress fidd in software ANSYS. In the numerical simulation mentioned above, three kinds of supporting, i.e. steel support, bolting support and non-support, were taken into account, the pressure distribution and defomaation state of roadways with a swelling rock floor under the coupling function of water and ground prressure were analyzed and compared with tbose in the action of only ground pressure. The research results provides a seientific basis for the deformation control of roadways in swelling rock.    

16.  Numerical Simulation of Multi-repaired Weld Residual Stress  
   ZHUYuan-xiang ZHAOXue-rong ZHANGXiao-fei HULun-ji《武汉理工大学学报(材料科学英文版)》,2004年第19卷第4期
   In order to understand the change regulation of resichual stress during muhi-repaired uelding to provide theoretical guidance for correct repaired welding procedure and improvement of joint properties.and to simulate the magnitude and distribution of residual stress using the finite element method (FEM).A model of temperature field of weld repaired using FEM,which was simplified,was established.the weld stress consists of ther mal stress and orgaization stress.models of the thermal stress and organization stress were described ANSYS, a software of finite element,was applied to calculate the stress,BHW35 steel was taken as an example,the simulated and experimental results for the 1 st ,3rd and 5th weldrepaired were analyzed,the simulated results are in good agreement with experimental results it can be concluded that the residual stress,in the weld center changes little,and the high residual stress exists in HAZ and in the same place the more repaired weld.the higher residual tress and the area of residual stress becomes wider.    

17.  Temperature control and cracking prevention in coastal thin-wall concrete structures  被引次数:1
   Li-xia GUO  Xiao-hong BAI  Ling ZHONG  Sheng QIANG《水科学与水工程》,2011年第4卷第4期
   A three-dimensional finite element program for thermal analysis of hydration heat in concrete structures with a plastic pipe cooling system is introduced in this paper. The program was applied to simulation of the temperature and stress field of the Cao’e Sluice during the construction period. From the calculated results, we can find that the temperature and stress of concrete cooled with plastic pipes are much lower than those of concrete without pipes. Moreover, plastic pipes could not be corroded by seaw...    

18.  STRESS ANALYSIS OF INJECTION MOLDED PARTS IN POST-FILLING STAGE  被引次数:1
   Jiang Tao《机械工程学报(英文版)》,2000年第1期
   0 INTRODUCTIONThe wmpage of injection molded parts is a difficult problem to the mold designers. There are manyfactors that cause Warpage, such as the technics of injection molding, the designing of mold and thematerial Of mold, etc. Inappropriate parameters of those factors can cause differential shrinkage of theparts during POst-filling and cooling stage, which may be the reason of the differential distribution of theresidual thermal stress. Then the residual stress will lead to waIPa…    

19.  Overall Evaluation of the Effect of Residual Stress Induced by Shot Peening in the Improvement of Fatigue Fracture Resistance for Metallic Materials  
   WANG Renzhi  RU Jilai《机械工程学报(英文版)》,2015年第2期
   Before 1980s,the circular suspension spring in automobile subjected to torsion fatigue load,under the cyclic normal tensile stresses,the majority of fatigue fracture occurred was in normal tensile fracture mode(NTFM)and the fracture surface was under 45°diagonal.Because there exists the interaction between the residual stresses induced by shot peening and the applied cyclic normal tensile stresses in NTFM,which represents as"stress strengthening mechanism",shot peening technology could be used for improving the fatigue fracture resistance(FFR)of springs.However,since 1990s up to date,in addition to regular NTFM,the fatigue fractures occurred of peened springs from time to time are in longitudinal shear fracture mode(LSFM)or transverse shear fracture mode(TSFM)with the increase of applied cyclic shear stresses,which leads to a remarkable decrease of FFR.However,LSFM/TSFM can be avoided effectively by means of shot peening treatment again on the peened springs.The phenomena have been rarely happened before.At present there are few literatures concerning this problem.Based upon the results of force analysis of a spring,there is no interaction between the residual stresses by shot peening and the applied cyclic shear stresses in shear fracture.This;means that the effect of"stress strengthening mechanism"for improving the FFR of LSFM/TSFM is disappeared basically.During shot peening,however,both of residual stress and cyclic plastic deformed microstructure are induced synchronously like"twins"in the surface layer of a spring.It has been found for the first time by means of force analysis and experimental results that the modified microstructure in the"twins"as a"structure strengthening mechanism"can improve the FFR of LSFM/TSFM.At the same time,it is;also shown that the optimum technology of shot peening strengthening must have both"stress strengthening mechanism"and"structure strengthening mechanism"simultaneously so that the FFR of both NTFM and LSFM/TSFM can be improved by shot peening.    

20.  An anisotropic thermal-stress model for through-silicon via  
   Song Liu  Guangbao Shan《半导体学报》,2018年第2期
   A two-dimensional thermal-stress model of through-silicon via (TSV) is proposed considering the anisotropic elastic property of the silicon substrate.By using the complex variable approach,the distribution of thermalstress in the substrate can be characterized more accurately.TCAD 3-D simulations are used to verify the model accuracy and well agree with analytical results (< ±5%).The proposed thermal-stress model can be integrated into stress-driven design flow for 3-D IC,leading to the more accurate timing analysis considering the thermal-stress effect.    

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