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Neumann stochastic finite element method for calculating temperature field of frozen soil based on random field theory 被引量:3
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作者 Tao Wang GuoQing Zhou 《Research in Cold and Arid Regions》 CSCD 2013年第4期488-497,共10页
To study the effect of uncertain factors on the temperature field of frozen soil, we propose a method to calculate the spatial average variance from just the point variance based on the local average theory of random ... To study the effect of uncertain factors on the temperature field of frozen soil, we propose a method to calculate the spatial average variance from just the point variance based on the local average theory of random fields. We model the heat transfer coefficient and specific heat capacity as spatially random fields instead of traditional random variables. An analysis for calculating the random temperature field of seasonal frozen soil is suggested by the Neumann stochastic finite element method, and here we provide the computational formulae of mathematical expectation, variance and variable coefficient. As shown in the calculation flow chart, the stochastic finite element calculation program for solving the random temperature field, as compiled by Matrix Laboratory (MATLAB) sottware, can directly output the statistical results of the temperature field of frozen soil. An example is presented to demonstrate the random effects from random field parameters, and the feasibility of the proposed approach is proven by compar- ing these results with the results derived when the random parameters are only modeled as random variables. The results show that the Neumann stochastic finite element method can efficiently solve the problem of random temperature fields of frozen soil based on random field theory, and it can reduce the variability of calculation results when the random parameters are modeled as spatial- ly random fields. 展开更多
关键词 fi'ozen soil Neumann expansion stochastic finite element method random temperature field
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Analysis Method of Transient Temperature Field for Fuel Tank ofHigh-Altitude Large UAV 被引量:1
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作者 Qing Ai Liang Chen +3 位作者 Xiaojing Xu Shiyu Liu Zhenwen Hu Xinlin Xia 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第6期41-46,共6页
Based on the analysis of factors affecting transient temperature field of aircraft fuel tank and coupled heat transfer mechanism, a mathematical model of transient coupled heat transfer, including the dynamic- chan... Based on the analysis of factors affecting transient temperature field of aircraft fuel tank and coupled heat transfer mechanism, a mathematical model of transient coupled heat transfer, including the dynamic- change of fuel quality, the internal heat transfer, the external aerodynamic convection and the radiation heat transfer, is established. Taking the aerodynamic convection and radiation heat transfer outside the tank as the third kinds of thermal boundary conditions for the thermal analysis of the fuel tank, calculation of internal and external coupling heat of fuel tank is decoupled. Ther^nal network method combined with hierarchical dynamic- grid is used to deal with the fuel consumption, and carry on the heat transfer analysis of the fuel tank. The numerical method for the transient temperature field of aircraft fuel tank is established. Through the simulation calculation, the transient temperature distribution of the fuel tank under different flight conditions is obtained, and the influence of the fuel mass and the external thermal environment on the temperature field is analyzed. 展开更多
关键词 unmanned aerial vehicle fuel tank transient temperature field numerical simulationCLC number TK16 Document code A Article ID 1005-9113(2016)06-0041-06
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Optimal Design Strategies of Femur Tumor Hyperthermia Based on Finite Element Analysis of Temperature Field
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作者 Monan Wang Lei Sun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第4期121-128,共8页
A 3D femoral model was built to obtain the three-dimensional temperature distribution of femur and its surrounding tissues and provide references for clinical applications. According to the relationship between gray-v... A 3D femoral model was built to obtain the three-dimensional temperature distribution of femur and its surrounding tissues and provide references for clinical applications. According to the relationship between gray-value and material properties,the model was assigned with various materials to make sure that it is more similar to the real femur in geometry and physical properties. 3D temperature distribution is obtained by using finite element analysis software ANSYS 11. 0 on the basis of heat conduction theory,Laplace equation,Pennes bio-heat transfer equation,thermo physical parameters of bone tissues,the boundary condition,and initial conditions. Taken the asymmetry of the 3D distribution of temperature into account,it is necessary to adopt the heating method with multiple heat sources. This method can ensure that the temperature fields match well with the tumor tissues and kill the tumor cells efficiently under the condition of protecting the normal tissues from damage. The analysis results supply important guidance for determining the needle position and the needle number and controlling the intensity of heating. 展开更多
关键词 FEMUR tumor hyperthermia 3D temperature fields finite element analysis
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Finite element analysis of temperature field during multi-layer multi-pass weld-based rapid prototyping 被引量:2
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作者 赵慧慧 张广军 +1 位作者 殷子强 吴林 《China Welding》 EI CAS 2011年第4期1-5,共5页
During weld-bused rapid prototyping, the component experiences complex thermal process. In this paper, the temperature field evolution, thermal cycle characteristics, and temperature gradients of multi-layer multi-pus... During weld-bused rapid prototyping, the component experiences complex thermal process. In this paper, the temperature field evolution, thermal cycle characteristics, and temperature gradients of multi-layer multi-puss weld-based rapid prototyping are investigated using three-dimensional finite element models presented. The single-puss weld-bused rapid prototyping experiment is carried out. Thermal cycles calculated agree with experimental measurements. Furthermore, simulated results indicate that there exist the pre-heating effect of the fore layer and the post-heating effect of the rear layer in the multi-layer multi-pass weld-based rapid prototyping. In the first layer, the heat accumulates obviously. After the first layer, the dimension increase of the high temperature region behind the molten pool is not obvious. The heat diffusion condition in the first layer is the best, the heat diffusion condition in the second layer is the worst, and the heat diffusion conditions in the higher layers improve gradually. 展开更多
关键词 temperature field finite element analysis weld-based rapid prototyping temperature gradient
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Finite element simulation of three-dimensional temperature field in underwater welding 被引量:1
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作者 刘习文 王国荣 +1 位作者 石永华 钟继光 《China Welding》 EI CAS 2007年第2期59-65,共7页
Mathematical models of three-dimensional temperature fields in underwater welding with moving heat sources are built. Double ellipsoid Gauss model is proposed as heat sources models. Several factors which affect the t... Mathematical models of three-dimensional temperature fields in underwater welding with moving heat sources are built. Double ellipsoid Gauss model is proposed as heat sources models. Several factors which affect the temperature fields of underwater welding are analyzed. Water has little influence on thermal efftciency. Water convection coefftcient varies with the temperature difference between the water and the workpiece , and water convection makes molten pool freeze quickly. With the increase of water depth, the dimensions of heat sources model should be reduced as arc shrinks. Finite element technology is used to solve mathematical models. ANSYS software is used as finite element tool, and ANSYS Parametric Design Language is used to develop subprograms for loading the moving heat sources and the various convection coefftcients. Experiment results show that computational results by using double ellipsoid Gauss heat sources model accord well with the experimental results. 展开更多
关键词 underwater welding temperature fields finite element method double ellipsoid Gauss heat sources model water convection
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Application of Wavelet Finite Element Method to Simulation of the Temperature Field of Copier Paper 被引量:1
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作者 YANGSheng-jun MAJun-xing 《International Journal of Plant Engineering and Management》 2002年第4期191-197,共7页
Simulation of the temperature field of copier paper in copier fusing is very important for improving the fusing property of reprography. The temperature field of copier paper varies with a high gradient when the copie... Simulation of the temperature field of copier paper in copier fusing is very important for improving the fusing property of reprography. The temperature field of copier paper varies with a high gradient when the copier paper is moving through the fusing rollers. By means of conventional shaft elements, the high gradient temperature variety causes the oscillation of the numerical solution. Based on the Daubechies scaling functions, a kind of wavelet based element is constructed for the above problem. The temperature field of the copier paper moving through the fusing rollers is simulated using the two methods. Comparison of the results shows the advantages of the wavelet finite element method, which provides a new method for improving the copier properties. 展开更多
关键词 copier paper temperature field wavelet finite element method SIMULATION
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Finite element analysis on temperature field and residual stress of welding assembly for I-beam and end-plate
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作者 贾栗 赵永生 +1 位作者 邹增大 邹勇料 《China Welding》 EI CAS 2013年第1期16-20,共5页
Based on full scale model of 1-beam and end-plate welding assembly with medium plate, welding temperature field and residual stress were simulated, infrared thermometers were employed to measure the real-time temperat... Based on full scale model of 1-beam and end-plate welding assembly with medium plate, welding temperature field and residual stress were simulated, infrared thermometers were employed to measure the real-time temperature Jbr verification purposes. Results show that the measured thermal cycle curves match well with the simulation result. Simulation results of welding residual stress indicate that the values of longitudinal and transverse stress on the upper surface of the plate are higher than the normal stress; higher tensile stresses exist at the end of the web weld toes and in the central area of the flange weld toes. The dangerous zones are located at the central areas of weld toes of the flange welds and near weld toes of the web welds. 展开更多
关键词 I-beam and end-plate welding assembly temperature field residual stress finite element analysis
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Vacuum electron beam brazing technology and finite element analysis on temperature field of capillary to plate joint
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作者 芦凤桂 唐新华 +2 位作者 梁智 李少青 姚舜 《China Welding》 EI CAS 2007年第2期5-10,共6页
Some parts with capillary to plate joint have important application in aerocrafi. Vacuum electron beam brazing (VEBB) technology is used to realize this jointing with capillaries. Firstly 3D finite element analysis ... Some parts with capillary to plate joint have important application in aerocrafi. Vacuum electron beam brazing (VEBB) technology is used to realize this jointing with capillaries. Firstly 3D finite element analysis model is built in this paper according to this special structure. And then ANSYS finite element analysis software is used to analyze brazing temperature field at different brazing parameters. The calculation results show that the temperature field of simulation has good agreement with that measured by experiment, which proves dependence of the model built in this paper. And also reference parameters could be provided for real brazing process through calculation in this model. Brazed joint of capiUary to plate with good performance is achieved using VEBB technology. The achievement of the study will be applied in aerocrafi in the future. 展开更多
关键词 capillary to plate joint finite element analysis vacuum electron beam brazing temperature field
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Study on Temperature Field of Surrounding Rock with BEM 被引量:1
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作者 吴强 秦跃平 +1 位作者 刘爱明 陈永权 《Journal of China University of Mining and Technology》 2001年第1期6-9,共4页
The authors analyzed the characteristic of surrounding rock temperature field around a drifting face, set up its mathematic model, and got its numerical result with the boundary element method(BEM). To calculate in tr... The authors analyzed the characteristic of surrounding rock temperature field around a drifting face, set up its mathematic model, and got its numerical result with the boundary element method(BEM). To calculate in tra domain integral, it was transformed into boundary integration with the DRM method. Using the similitude theory, the dimensionless differential equation was educed. Finally, the authors calculated two drifting faces of Sanhejian Coal Mine using the computer software developed by authors based on the above principium, and got the distribution characteristic of surrounding rock temperature field around a drifting face and the periodic variation in temperature with its periodic moving forward. Comparing the calculated heat dissipating capacity of surrounding rock with the measured data shows that the computer software is proper. 展开更多
关键词 drifting face surrounding rock temperature field boundary element method
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Manufacture of HTR Fuel Element
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作者 Shijiang, X. Chunhe, T. +3 位作者 Zhichang, X. Junguo, Zh. Xueliang, Q. Ende, L. 《High Technology Letters》 EI CAS 1995年第1期87-90,共4页
The HTR Fuel Element R & D Program,set in 1987,aims to develop the manufacturetechnology of HTR fuel element and to produce the fuel element for the first core of our 10MW experimental reactor.Now the work on labo... The HTR Fuel Element R & D Program,set in 1987,aims to develop the manufacturetechnology of HTR fuel element and to produce the fuel element for the first core of our 10MW experimental reactor.Now the work on laboratory scale is phased out.In this paper,the fuel element manufacture technology is described and the test results are given. 展开更多
关键词 High temperature reactor Coated fuel particles Spherical fuel element Irradiation qualification
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Numerical simulation of roll temperature field and analysis of influence factor during the single-stand reversing cold rolling process
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作者 DAI Jingge WANG Kangfian 《Baosteel Technical Research》 CAS 2017年第4期1-8,共8页
Accurate calculation results of roll temperature are the key factors in rolling cooling and lubricating technology during the single-stand reversing cold rolling process. By combining the high-strength steel rolling e... Accurate calculation results of roll temperature are the key factors in rolling cooling and lubricating technology during the single-stand reversing cold rolling process. By combining the high-strength steel rolling experiments ,the numerical simulation of roll temperature, and the influence factors in reversing cold rolling were studied. The research results correspond with those of rolling experiments and show that the research method could provide effective instruction for roll cooling and emulsion flow rate control during the on-site rolling process. 展开更多
关键词 cold rolled high-strength steel roll temperature field finite element modeling heat transfercoefficient
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Numerical Simulation of Temperature Field and Thermal Stress Field of Work Roll During Hot Strip Rolling 被引量:13
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作者 LI Chang-sheng YU Hai-liang DENG Guan-yu LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第5期18-21,共4页
Based on the thermal conduction equations, the three-dimensional (3D) temperature field of a work roll was investigated using finite element method (FEM). The variations in the surface temperature of the work roll... Based on the thermal conduction equations, the three-dimensional (3D) temperature field of a work roll was investigated using finite element method (FEM). The variations in the surface temperature of the work roll during hot strip rolling were described, and the thermal stress field of the work roll was also analyzed. The results showed that the highest roll surface temperature is 593 ℃, and the difference between the minimum and maximum values of thermal stress of the work roll surface is 145.7 MPa. Furthermore, the results of this analysis indicate that temperature and thermal stress are useful parameters for the investigation of roll thermal fatigue and also for improving the quality of strip during rolling. 展开更多
关键词 hot strip mill ROLL temperature field thermal stress finite element method
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THE COUPLED FEM ANALYSIS OF THE TRANSIENT TEMPERATURE FIELD DURING INERTIA FRICTION WELDING OF GH4169 ALLOY 被引量:8
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作者 L.W. Zhang J.B. Pei +4 位作者 Q.Z. Zhang C.D. Liu W.H. Zhu S. Qu J.H. Wang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2007年第4期301-306,共6页
The inertia friction welding process is a non-linear process because of the interaction between the temperature field and the material properties as well as the friction force. A thermo-mechanical coupled finite eleme... The inertia friction welding process is a non-linear process because of the interaction between the temperature field and the material properties as well as the friction force. A thermo-mechanical coupled finite element model is established to simulate the temperature field of this process. The transient temperature distribution during the inertia friction welding process of two similar workpieces of GH4169 alloy is calculated. The region of the circular cross-section of the workpiece is divided into a number of four-nodded isoparametric elements. In this model, the temperature dependent thermal properties, time dependent heat inputs, contact condition of welding interface, and deformation of the flash were considered. At the same time, the convection and radiation heat losses at the surface of the workpieces were also considered. A temperature data acquisition system was developed. The temperature at some position near the welding interface was measured using this system. The calculated temperature agrees well with the experimental data. The deformation of the flash and the factor affecting the temperature distribution at the welding interface are also discussed. 展开更多
关键词 inertia friction welding temperature field numerical simulation finite element method
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Numerical simulation of temperature fields for T-joint during TIG welding of titanium alloy 被引量:7
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作者 王敏 董志波 +1 位作者 于澜 魏艳红 《China Welding》 EI CAS 2008年第3期6-9,共4页
Three-dimensional finite element model was established to simulate temperature fields of T-joint titanium sheets during TIG welding with finite element method (FEM) software. Temperature dependent material propertie... Three-dimensional finite element model was established to simulate temperature fields of T-joint titanium sheets during TIG welding with finite element method (FEM) software. Temperature dependent material properties and the effect of latent heat were considered. A technique of element birth and death was used to simulate the process of welded metal filling. Dynamic variation process of temperature fields during T1G welding was achieved. The simulated results agreed well with the measured results. 展开更多
关键词 TIG welding TITANIUM T-JOINT temperature field finite element method
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Numerical simulation on temperature field for resistance spot welding of non-equal thickness stainless steel 被引量:8
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作者 王春生 陈勇 +2 位作者 韩凤武 陆培德 姜中辉 《China Welding》 EI CAS 2003年第1期6-10,共5页
An axisymmetric finite element model is developed to simulate the temperature field of resistant spot welding according to the process characters of nugget formation of non equal stainless steel sheets. A simulation ... An axisymmetric finite element model is developed to simulate the temperature field of resistant spot welding according to the process characters of nugget formation of non equal stainless steel sheets. A simulation method of the interaction of electrical and thermal factors is presented. The spot welding process of nugget formation is simulated using hard and soft welding technique norms. The heating characters of soft and hard norms determine the differences in the process of nugget formation and determine the finally shape and offset of nugget. Experimental verification shows that the model prediction agrees well with the practical. 展开更多
关键词 resistance spot welding finite element temperature field numerical simulation
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Numerical simulation of wellbore and formation temperature fields in carbonate formations during drilling and shut-in in the presence of lost circulation 被引量:3
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作者 Pan Baozhi Li Ding +3 位作者 Chen Gang Wang Qincong Ma Lixin Liu Sihui 《Petroleum Science》 SCIE CAS CSCD 2014年第2期293-299,共7页
Temperature curves reflect geothermal gradients and local temperature anomalies, thus providing a new understanding of the underground reservoir conditions. When encountering caverns or fractures and fissures during d... Temperature curves reflect geothermal gradients and local temperature anomalies, thus providing a new understanding of the underground reservoir conditions. When encountering caverns or fractures and fissures during drilling, lost circulation may occur and result in a change to the original formation temperature field, and in severe cases, even the conventional open hole well logging data cannot be obtained. This paper uses finite element analysis software COMSOL to establish a heat transfer model for the wellbore/reservoir formation system during drilling and shut-in in the presence of lost circulation, and a case study is made in a carbonate reservoir in the Tahe oilfield. On the basis of the above, we analyze the temperature distribution in the leakage zone, and the studies have shown that the leakage and petrophysical properties have an impact on the temperature of the wellbore and formation, hence we can estimate the reservoir permeability using the temperature data. In addition, the determination of the temperature recovery time after some drilling fluids have leaked into the formation will help in recognizing the subsurface temperature field of the carbonate formation correctly, thus enhancing production logging interpretation accuracy and improving the understanding of later measurements. 展开更多
关键词 temperature field numerical simulation finite element drilling fluid invasion LEAKAGE
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FEM simulations and experimental studies of the temperature field in a large diamond crystal growth cell 被引量:4
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作者 李战厂 贾晓鹏 +4 位作者 黄国锋 胡美华 李勇 颜丙敏 马红安 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期363-367,共5页
We investigate the temperature field variation in the growth region of a diamond crystal in a sealed cell during the whole process of crystal growth by using the temperature gradient method (TGM) at high pressure an... We investigate the temperature field variation in the growth region of a diamond crystal in a sealed cell during the whole process of crystal growth by using the temperature gradient method (TGM) at high pressure and high temperature (HPHT). We employ both the finite element method (FEM) and in situ experiments. Simulation results show that the temperature in the center area of the growth cell continues to decrease during the process of large diamond crystal growth. These results are in good agreement with our experimental data, which demonstrates that the finite element model can successfully predict the temperature field variations in the growth cell. The FEM simulation will be useful to grow larger high-quality diamond crystal by using the TGM. Furthermore, this method will be helpful in designing better cells and improving the growth process of gem-quality diamond crystal. 展开更多
关键词 temperature field finite element method single crystal growth diamond
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Effects of Process Parameters on the Temperature Field in Ti-6Al-4V Alloy Blade Precision Forging Process 被引量:2
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作者 Yuli LIU He YANG Tao GAO Mei ZHAN 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第4期473-477,共5页
Blade precision forging is a high temperature and large plastic deformation process. Process parameters have a great effect on temperature distribution in billet, so in this paper, by taking a Ti-6Al-4V alloy blade wi... Blade precision forging is a high temperature and large plastic deformation process. Process parameters have a great effect on temperature distribution in billet, so in this paper, by taking a Ti-6Al-4V alloy blade with a tenon as an object, the influence of process parameters on the temperature distribution in precision forging process was investigated using 3D coupled thermo-mechanical FEM (finite element method) code developed by the authors. The results obtained illustrate that: (1) the gradient of temperature distribution increases with increasing the deformation degree; (2) with increasing the initial temperature of the billet, the zones of high temperature become larger, and the gradient of temperature distribution hardly has any increase; (3) friction factors have little effect on the distribution of temperature field; (4) with increasing upper die velocity, temperature of the billet increases while the temperature gradient in billet decreases. The results are helpful to the design and optimization of the process parameters in precision forging process of Ti-alloy blade. 展开更多
关键词 Ti-alloy blade Precision forging Process parameter temperature field Finite element method (FEM)
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MATHEMATICAL MODEL OF MILLING TEMPERATURE AND TEMPERATURE FIELD ANALYSIS FOR THREE-DIMEN-SIONAL COMPLEX GROOVE MILLING INSERT 被引量:1
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作者 Li ZhenjiaDong LihuaTan GuangyuGuo QiangCheng YaonanCollege of Mechanical Engineering,Harbin University of Scienceand Technology,Harbin 150080, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第4期340-343,共4页
The mathematical model on the temperature of the waved-edge is constructedaccording to Jaeger's theory of moving solid and based on the used temperature model of the flatinsert. It is possible to forecast the mill... The mathematical model on the temperature of the waved-edge is constructedaccording to Jaeger's theory of moving solid and based on the used temperature model of the flatinsert. It is possible to forecast the milling temperature through programming. The comparableexperiments have been done between the two new three-dimension groove inserts (waved-edge insert,great edge insert) and flat fake insert. The theoretic forecast is in good agreement with theexperimental result. According to the cutting conditions, the boundary condition of finite elementanalysis on cutting temperature field is established, and the three-dimensional temperature fieldsof inserts with grooves are analyzed by FEM, so as to offer a reference basis for the design andoptimization of insert grooves. 展开更多
关键词 Three-dimensional groove milling insert Cutting temperature mathematicalmodel temperature field Finite element analysis
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3D Eddy Current and Temperature Field Analysis of Large Hydro-generators in Leading Phase Operations 被引量:5
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作者 Ning Wang Huifang Wang Shiyou Yang 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第2期210-215,共6页
As a common practice,a large hydro-generator will operate in leading phase conditions to absorb the reactive power of the power grid.However,the accurate and precise prediction of the leading phase operation capacity ... As a common practice,a large hydro-generator will operate in leading phase conditions to absorb the reactive power of the power grid.However,the accurate and precise prediction of the leading phase operation capacity of a large hydro-generator has always been a formidable challenge to engineers and academicians because it is extremely hard to compute the eddy currents and losses as well as the local overheating in the pressure plate and finger.To address this problem,a full three dimensional(3D)finite element model and method of the coupled eddy current and temperature fields in the end region of a large hydro-generator are developed.The equivalent medium parameters used in the computations are comprehensively discussed.Moreover,some numerically based solution methodologies for accurate computation of the field and armature currents under different leading phase conditions are proposed.Numerical results on the coupled eddy current and temperature fields in the end regions of a 250 MW hydro-generator confirm positively the feasibility of the present work. 展开更多
关键词 Eddy current field HYDRO-GENERATOR 3D finite element method temperature field.
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