期刊文献+
共找到13,845篇文章
< 1 2 250 >
每页显示 20 50 100
Three-dimensional Finite Element Modeling of a Maxillary Premolar Tooth Based on the Micro-CT Scanning: A Detailed Description 被引量:4
1
作者 黄政 陈智 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第5期775-779,共5页
This study describes the details of how to construct a three-dimensional (3D) finite element model of a maxillary first premolar tooth based on micro-CT data acquisition technique, MIMICS soft- ware and ANSYS softwa... This study describes the details of how to construct a three-dimensional (3D) finite element model of a maxillary first premolar tooth based on micro-CT data acquisition technique, MIMICS soft- ware and ANSYS software. The tooth was scanned by micro-CT, in which 1295 slices were obtained and then 648 slices were selected for modeling. The 3D surface mesh models of enamel and dentin were created by MIMICS (STL file). The solid mesh model was constructed by ANSYS. After the material properties and boundary conditions were set, a loading analysis was performed to demonstrate the ap- plicableness of the resulting model. The first and third principal stresses were then evaluated. The re- suits showed that the number of nodes and elements of the finite element model were 56 618 and 311801, respectively. The geometric form of the model was highly consistent with that of the true tooth, and the deviation between them was ~).28%. The loading analysis revealed the typical stress patterns in the contour map. The maximum compressive stress existed in the contact points and the maximum tensile stress existed in the deep fissure between the two cusps. It is concluded that by using the micro-CT and highly integrated software, construction of the 3D finite element model with high quality will not be difficult for clinical researchers. 展开更多
关键词 three-dimensional finite element MICRO-CT PREMOLAR MIMICS ANSYS
下载PDF
Evaluation value of three-dimensional finite element model analysis for bone mineral density and bone metabolism activity in patients with osteoporosis
2
作者 Wei Qi Ya-Bo Yan +3 位作者 Wei Fu Bing Hao Shen-Ke Yang Shao-Qi Chen 《Journal of Hainan Medical University》 2017年第16期138-141,共4页
Objective: To study the evaluation value of three-dimensional finite element model analysis for bone mineral density (BMD) and bone metabolism activity in patients with osteoporosis. Methods: A total of 218 patients w... Objective: To study the evaluation value of three-dimensional finite element model analysis for bone mineral density (BMD) and bone metabolism activity in patients with osteoporosis. Methods: A total of 218 patients who were diagnosed with osteoporosis in the hospital between February 2014 and January 2017 were collected as observation group, and 100 healthy volunteers who received physical examination in the hospital during the same period were selected as normal control group. The femoral head of the two groups was analyzed by three-dimensional finite element model, and the femoral head BMD levels and serum bone metabolism index contents were measured. Pearson test was used to evaluate the evaluation value of femoral head three-dimensional finite element model for osteoporosis. Results: The cancellous bone and cortical bone Von Mises stress value of observation group were lower than those of normal control group, and femoral neck BMD value of observation group was lower than that of normal control group;serum bone metabolism index BGP content was lower than that of normal control group while NBAP, TRACP-5b and CTX-1 contents were higher than those of normal control group. Pearson test showed that the cancellous bone and cortical bone Von Mises stress value of patients with osteoporosis were directly correlated with BMD value and bone metabolism index contents. Conclusion: The three-dimensional finite element model analysis resultsof patients with osteoporosis can objectively reflect the femoral headBMD value and bone metabolism activity, and is a reliable way to evaluate the risk of long-term fractures. 展开更多
关键词 OSTEOPOROSIS three-dimensional finite element model analysis BONE MINERAL density BONE METABOLISM
下载PDF
Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions
3
作者 Jiaqi Wu Li Zhuo +4 位作者 Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期621-645,共25页
The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling ... The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical modeling.To improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python codes.The basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web platform.The modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling parameters.The main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric models.In particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling program.Themodularized and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower Station.This complicatedmodel is rapidly generated for the simulation,and the simulation results are reasonable.Thus,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses. 展开更多
关键词 Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling
下载PDF
Multi-scale Modeling and Finite Element Analyses of Thermal Conductivity of 3D C/SiC Composites Fabricating by Flexible-Oriented Woven Process
4
作者 Zheng Sun Zhongde Shan +5 位作者 Hao Huang Dong Wang Wang Wang Jiale Liu Chenchen Tan Chaozhong Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期275-288,共14页
Thermal conductivity is one of the most significant criterion of three-dimensional carbon fiber-reinforced SiC matrix composites(3D C/SiC).Represent volume element(RVE)models of microscale,void/matrix and mesoscale pr... Thermal conductivity is one of the most significant criterion of three-dimensional carbon fiber-reinforced SiC matrix composites(3D C/SiC).Represent volume element(RVE)models of microscale,void/matrix and mesoscale proposed in this work are used to simulate the thermal conductivity behaviors of the 3D C/SiC composites.An entirely new process is introduced to weave the preform with three-dimensional orthogonal architecture.The 3D steady-state analysis step is created for assessing the thermal conductivity behaviors of the composites by applying periodic temperature boundary conditions.Three RVE models of cuboid,hexagonal and fiber random distribution are respectively developed to comparatively study the influence of fiber package pattern on the thermal conductivities at the microscale.Besides,the effect of void morphology on the thermal conductivity of the matrix is analyzed by the void/matrix models.The prediction results at the mesoscale correspond closely to the experimental values.The effect of the porosities and fiber volume fractions on the thermal conductivities is also taken into consideration.The multi-scale models mentioned in this paper can be used to predict the thermal conductivity behaviors of other composites with complex structures. 展开更多
关键词 3D C/SiC composites finite element analyses Multi-scale modeling Thermal conductivity
下载PDF
In silico optimization of actuation performance in dielectric elastomercomposites via integrated finite element modeling and deep learning
5
作者 Jiaxuan Ma Sheng Sun 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期48-56,共9页
Dielectric elastomers(DEs)require balanced electric actuation performance and mechanical integrity under applied voltages.Incorporating high dielectric particles as fillers provides extensive design space to optimize ... Dielectric elastomers(DEs)require balanced electric actuation performance and mechanical integrity under applied voltages.Incorporating high dielectric particles as fillers provides extensive design space to optimize concentration,morphology,and distribution for improved actuation performance and material modulus.This study presents an integrated framework combining finite element modeling(FEM)and deep learning to optimize the microstructure of DE composites.FEM first calculates actuation performance and the effective modulus across varied filler combinations,with these data used to train a convolutional neural network(CNN).Integrating the CNN into a multi-objective genetic algorithm generates designs with enhanced actuation performance and material modulus compared to the conventional optimization approach based on FEM approach within the same time.This framework harnesses artificial intelligence to navigate vast design possibilities,enabling optimized microstructures for high-performance DE composites. 展开更多
关键词 Dielectric elastomer composites Multi-objective optimization finite element modeling Convolutional neural network
下载PDF
Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils
6
作者 Belemdara Dingamadji Hilaire Mbaïnaïbeye Jérôme Guidkaya Golam 《Journal of Electromagnetic Analysis and Applications》 2024年第2期11-23,共13页
The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the tw... The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet. 展开更多
关键词 modelLING 3D finite elements Magnetic Flux Hybrid Stepping Motor
下载PDF
Autologous nerve graft repair of different degrees of sciatic nerve defect:stress and displacement at the anastomosis in a three-dimensional finite element simulation model 被引量:1
7
作者 Cheng-dong Piao Kun Yang +1 位作者 Peng Li Min Luo 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第5期804-807,共4页
In the repair of peripheral nerve injury using autologous or synthetic nerve grafting, the mag- nitude of tensile forces at the anastomosis affects its response to physiological stress and the ultimate success of the ... In the repair of peripheral nerve injury using autologous or synthetic nerve grafting, the mag- nitude of tensile forces at the anastomosis affects its response to physiological stress and the ultimate success of the treatment. One-dimensional stretching is commonly used to measure changes in tensile stress and strain; however, the accuracy of this simple method is limited. There- fore, in the present study, we established three-dimensional finite element models of sciatic nerve defects repaired by autologous nerve grafts. Using PRO E 5.0 finite element simulation software, we calculated the maximum stress and displacement of an anastomosis under a 5 N load in 10-, 20-, 30-, 40-mm long autologous nerve grafts. We found that maximum displacement increased with graft length, consistent with specimen force. These findings indicate that three-dimensional finite element simulation is a feasible method for analyzing stress and displacement at the anas- tomosis after autologous nerve grafting. 展开更多
关键词 nerve regeneration sciatic nerve injury autologous nerve grafting epineurial suturing three-dimensional finite element models load stress DISPLACEMENT neural regeneration
下载PDF
Three-dimensional forward modeling for magnetotelluric sounding by finite element method 被引量:3
8
作者 童孝忠 柳建新 +3 位作者 谢维 徐凌华 郭荣文 程云涛 《Journal of Central South University》 SCIE EI CAS 2009年第1期136-142,共7页
A finite element algorithm combined with divergence condition was presented for computing three-dimensional(3D) magnetotelluric forward modeling. The finite element equation of three-dimensional magnetotelluric forwar... A finite element algorithm combined with divergence condition was presented for computing three-dimensional(3D) magnetotelluric forward modeling. The finite element equation of three-dimensional magnetotelluric forward modeling was derived from Maxwell's equations using general variation principle. The divergence condition was added forcedly to the electric field boundary value problem, which made the solution correct. The system of equation of the finite element algorithm was a large sparse, banded, symmetric, ill-conditioned, non-Hermitian complex matrix equation, which can be solved using the Bi-CGSTAB method. In order to prove correctness of the three-dimensional magnetotelluric forward algorithm, the computed results and analytic results of one-dimensional geo-electrical model were compared. In addition, the three-dimensional magnetotelluric forward algorithm is given a further evaluation by computing COMMEMI model. The forward modeling results show that the algorithm is very efficient, and it has a lot of advantages, such as the high precision, the canonical process of solving problem, meeting the internal boundary condition automatically and adapting to all kinds of distribution of multi-substances. 展开更多
关键词 magnetotelluric sounding three-dimensional forward modeling finite element method general variation principle divergence condition
下载PDF
Three-Dimensional Reconstructed Finite Element Model for C/C Composites by Micro-CT 被引量:3
9
作者 张海军 周储伟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第6期639-645,共7页
The precise microscopic feature of carbon-carbon(C/C) composites is essential {or an accurate predic tion of their mechanical behavior. After fabrication, actual microscopic feature differs from simple ideal spatial... The precise microscopic feature of carbon-carbon(C/C) composites is essential {or an accurate predic tion of their mechanical behavior. After fabrication, actual microscopic feature differs from simple ideal spatial model. Micro computed lomography(CT) scan can well describe internal microstruetures of composites. Therefore, a reconstructed model is developed based on mireo-CT, by a series of prodcedures including extrac tlng components, generating new binary images and establishing a finite element (FE) model. Compared with the model designed by reconstructed commercial software MIMICS. the presented reconstructed FE model is superior in terms of high mesh quality and eontrollable mesh cluantity. The precision of the model is verified by experiment. 展开更多
关键词 C/C composites mirco-CF binary image reconstructed procedure finite element model
下载PDF
Patient-specific modeling of facial soft tissue based on radial basis functions transformations of a standard three-dimensional finite element model 被引量:2
10
作者 LOU Hang-di CHEN Si CHEN Gui XU Tian-min RONG Qi-guo 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第22期4066-4071,共6页
Background An important purpose of orthodontic treatment is to gain the harmonic soft tissue profile. This article describes a novel way to build patient-specific models of facial soft tissues by transforming a standa... Background An important purpose of orthodontic treatment is to gain the harmonic soft tissue profile. This article describes a novel way to build patient-specific models of facial soft tissues by transforming a standard finite element (FE) model into one that has two stages: a first transformation and a second transformation, so as to evaluate the facial soft tissue changes after orthodontic treatment for individual patients. Methods The radial basis functions (RBFs) interpolation method was used to transform the standard FE model into a patient-specific one based on landmark points. A combined strategy for selecting landmark points was developed in this study: manually for the first transformation and automatically for the second transformation. Four typical patients were chosen to validate the effectiveness of this transformation method. Results The results showed good similarity between the transformed FE models and the computed tomography (CT) models. The absolute values of average deviations were in the range of 0.375-0.700 mm at the lip-mouth region after the first transformation, and they decreased to a range of 0.116-0.286 mm after the second transformation. Conclusions The modeling results show that the second transformation resulted in enhanced accuracy compared to the first transformation. Because of these results, a third transformation is usually not necessary. 展开更多
关键词 finite element model facial soft tissue model transformation radial basis functions landmark points
原文传递
Three-Dimensional Simulations of RESET Operation in Phase-Change Random Access Memory with Blade-Type Like Phase Change Layer by Finite Element Modeling 被引量:2
11
作者 金秋雪 刘波 +8 位作者 刘燕 王维维 汪恒 许震 高丹 王青 夏洋洋 宋志棠 封松林 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期128-131,共4页
An optimized device structure for reducing the RESET current of phase-change random access memory (PCRAM) with blade-type like (BTL) phase change layer is proposed. The electrical thermal analysis of the BTL cell ... An optimized device structure for reducing the RESET current of phase-change random access memory (PCRAM) with blade-type like (BTL) phase change layer is proposed. The electrical thermal analysis of the BTL cell and the blade heater contactor structure by three-dimensional finite element modeling are compared with each other during RESET operation. The simulation results show that the programming region of the phase change layer in the BTL cell is much smaller, and thermal electrical distributions of the BTL cell are more concentrated on the TiN/GST interface. The results indicate that the BTL cell has the superiorities of increasing the heating efficiency, decreasing the power consumption and reducing the RESET current from 0.67mA to 0.32mA. Therefore, the BTL cell will be appropriate for high performance PCRAM device with lower power consumption and lower RESET current. 展开更多
关键词 PCRAM cell RESET three-dimensional Simulations of RESET Operation in Phase-Change Random Access Memory with Blade-Type Like Phase Change Layer by finite element modeling of by in with
下载PDF
Three-Dimensional Thermo-Elastic-Plastic Finite Element Method Modeling for Predicting Weld-Induced Residual Stresses and Distortions in Steel Stiffened-Plate Structures 被引量:1
12
作者 Myung Su Yi Chung Min Hyun Jeom Kee Paik 《World Journal of Engineering and Technology》 2018年第1期176-200,共25页
The objective of the present paper is to develop nonlinear finite element method models for predicting the weld-induced initial deflection and residual stress of plating in steel stiffened-plate structures. For this p... The objective of the present paper is to develop nonlinear finite element method models for predicting the weld-induced initial deflection and residual stress of plating in steel stiffened-plate structures. For this purpose, three-dimensional thermo-elastic-plastic finite element method computations are performed with varying plate thickness and weld bead length (leg length) in welded plate panels, the latter being associated with weld heat input. The finite element models are verified by a comparison with experimental database which was obtained by the authors in separate studies with full scale measurements. It is concluded that the nonlinear finite element method models developed in the present paper are very accurate in terms of predicting the weld-induced initial imperfections of steel stiffened plate structures. Details of the numerical computations together with test database are documented. 展开更多
关键词 STEEL Stiffened-Plate Structures Weld-Induced Initial Distortion Weld-Induced Residual Stress Nonlinear finite element Method three-dimensional Ther-mo-Elastic-Plastic finite element Analysis Full Scale Measurements
下载PDF
An ultrasound-guided percutaneous electrical nerve stimulation regimen devised using finite element modeling promotes functional recovery after median nerve transection 被引量:3
13
作者 Xiao-Lei Chu Xi-Zi Song +5 位作者 Yu-Ru Li Zi-Ren Wu Qi Li Qing-Wen Li Xiao-Song Gu Dong Ming 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期683-688,共6页
Percutaneous electrical nerve stimulation of an injured nerve can promote and accelerate peripheral nerve regeneration and improve function.When performing acupuncture and moxibustion,locating the injured nerve using ... Percutaneous electrical nerve stimulation of an injured nerve can promote and accelerate peripheral nerve regeneration and improve function.When performing acupuncture and moxibustion,locating the injured nerve using ultrasound before percutaneous nerve stimulation can help prevent further injury to an already injured nerve.However,stimulation parameters have not been standardized.In this study,we constructed a multi-layer human forearm model using finite element modeling.Taking current density and activated function as optimization indicators,the optimal percutaneous nerve stimulation parameters were established.The optimal parameters were parallel placement located 3 cm apart with the injury site at the midpoint between the needles.To validate the efficacy of this regimen,we performed a randomized controlled trial in 23 patients with median nerve transection who underwent neurorrhaphy.Patients who received conventional rehabilitation combined with percutaneous electrical nerve stimulation experienced greater improvement in sensory function,motor function,and grip strength than those who received conventional rehabilitation combined with transcutaneous electrical nerve stimulation.These findings suggest that the percutaneous electrical nerve stimulation regimen established in this study can improve global median nerve function in patients with median nerve transection. 展开更多
关键词 finite element modeling median nerve transection nerve regeneration NEUROREHABILITATION percutaneous electrical nerve stimulation peripheral nerve injury randomized controlled trial
下载PDF
Study on hot deformation behavior of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy using a combination of strain-compensated Arrhenius constitutive model and finite element simulation method 被引量:2
14
作者 Li Hu Mengwei Lang +4 位作者 Laixin Shi Mingao Li Tao Zhou Chengli Bao Mingbo Yang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第3期1016-1028,共13页
Isothermal hot compression experiments were conducted on homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy to investigate hot deformation behavior at the temperature range of 673-773 K and the strain rate range of 0.001-1 s... Isothermal hot compression experiments were conducted on homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy to investigate hot deformation behavior at the temperature range of 673-773 K and the strain rate range of 0.001-1 s^(-1)by using a Gleeble-1500D thermo mechanical simulator.Metallographic characterization on samples deformed to true strain of 0.70 illustrates the occurrence of flow localization and/or microcrack at deformation conditions of 673 K/0.01 s^(-1),673 K/1 s^(-1)and 698 K/1 s^(-1),indicating that these three deformation conditions should be excluded during hot working of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy.Based on the measured true stress-strain data,the strain-compensated Arrhenius constitutive model was constructed and then incorporated into UHARD subroutine of ABAQUS software to study hot deformation process of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy.By comparison with measured force-displacement curves,the predicted results can describe well the rheological behavior of homogenized Mg-8.5Gd-4.5Y-0.8Zn-0.4Zr alloy,verifying the validity of finite element simulation of hot compression process with this complicated constitutive model.Numerical results demonstrate that the distribution of values of material parameters(α,n,Q and ln A)within deformed sample is inhomogeneous.This issue is directly correlated to the uneven distribution of equivalent plastic strain due to the friction effect.Moreover,at a given temperature the increase of strain rate would result in the decrease of equivalent plastic strain within the central region of deformed sample,which hinders the occurrence of dynamic recrystallization(DRX). 展开更多
关键词 Mg-RE-Zn alloy Hot deformation Microstructure evolution Constitutive model finite element simulation
下载PDF
Finite Element Simulation of Radial Tire Building and Shaping Processes Using an Elasto-Viscoplastic Model 被引量:1
15
作者 Yinlong Wang Zhao Li +1 位作者 Ziran Li Yang Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1187-1208,共22页
The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investiga... The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates.Based on the experiments,an elastoviscoplastic constitutive model is adopted to describe themechanical behaviors of the uncured rubber.The distinct mechanical properties,including the stress level,hysteresis and residual strain,of the uncured rubber can all be well characterized.The whole tire building process(including component winding,rubber bladder inflation,component stitching and carcass band folding-back)and the shaping process are simulated using this constitutive model.The simulated green tire profile is in good agreement with the actual profile obtained through 3D scanning.The deformation and stress of the rubber components and the cord reinforcements during production can be obtained fromthe FE simulation,which is helpful for judging the rationality of the tire construction design.Finally,the influence of the parameter“drum width”is investigated,and the simulated result is found to be consistent with the experimental observations,which verifies the effectiveness of the simulation.The established simulation strategy provides some guiding significance for the improvement of tire design parameters and the elimination of tire production defects. 展开更多
关键词 Uncured rubber constitutive modeling radial tire building process finite element method
下载PDF
Three-dimensional anisotropic induced polarization modeling using finite element method
16
作者 Junjie Liu Xiaoping Wu 《Earthquake Research Advances》 CSCD 2021年第S01期49-52,共4页
With the development of geophysical exploration technology,the anisotropy of underground media has got more and more attention.At present,there are few studies on the anisotropy of the induced polarization method.This... With the development of geophysical exploration technology,the anisotropy of underground media has got more and more attention.At present,there are few studies on the anisotropy of the induced polarization method.This article explores the effect of anisotropy on the underground media of the induced polarization method under three-dimensional complex terrain.The research work transforms the underground electric field control equation into a variational problem,and use the unstructured finite element method to construct a large linear equation system for solving electric potentials.By the sparse matrix compression technique and symmetric successive over-relaxation preconditioned conjugate gradient algorithm(SSOR-PCG)to solve the equation system.Finally,the article uses the classic central gradient array method to obtain the forward apparent polarizability value.The calculation results of the model find that different anisotropic conditions will significantly affect the forward results which show a strong directional correlation,revealing the importance of considering anisotropy in practical work. 展开更多
关键词 three-dimensional anisotropic finite element method
下载PDF
Finite Element Implementation of the Exponential Drucker-Prager Plasticity Model for Adhesive Joints
17
作者 Kerati Suwanpakpraek Baramee Patamaprohm +1 位作者 Sacharuck Pornpeerakeat Arisara Chaikittiratana 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期1765-1778,共14页
This paper deals with the numerical implementation of the exponential Drucker-Parger plasticitymodel in the commercial finite element software,ABAQUS,via user subroutine UMAT for adhesive joint simulations.The influen... This paper deals with the numerical implementation of the exponential Drucker-Parger plasticitymodel in the commercial finite element software,ABAQUS,via user subroutine UMAT for adhesive joint simulations.The influence of hydrostatic pressure on adhesive strength was investigated by a modified Arcan fixture designed particularly to induce a different state of hydrostatic pressure within an adhesive layer.The developed user subroutine UMAT,which utilizes an associated plastic flow during a plastic deformation,can provide a good agreement between the simulations and the experimental data.Better numerical stability at highly positive hydrostatic pressure loads for a very high order of exponential function can also be achieved compared to when a non-associated flow is used. 展开更多
关键词 Exponential Drucker-Prager model modified-Arcan test finite element analysis plastic potential function
下载PDF
A rigid-flexible coupling finite element model of coupler for analyzing train instability behavior during collision
18
作者 Jingke Zhang Tao Zhu +5 位作者 Bing Yang Xiaorui Wang Shoune Xiao Guangwu Yang Yanwen Liu Quanwei Che 《Railway Engineering Science》 2023年第4期325-339,共15页
Rail vehicles generate huge longitudinal impact loads in collisions.If unreasonable matching exists between the compressive strength of the intermediate coupler and the structural strength of the car body,the risk of ... Rail vehicles generate huge longitudinal impact loads in collisions.If unreasonable matching exists between the compressive strength of the intermediate coupler and the structural strength of the car body,the risk of car body structure damage and train derailment will increase.Herein,a four-stage rigid-flexible coupling finite element model of the coupler is established considering the coupler buckling load.The influence of the coupler buckling load on the train longitudinal-vertical-hori-zontal buckling behavior was studied,and the mechanism of the train horizontal buckling instability in train collisions was revealed.Analysis results show that an intermediate coupler should be designed to ensure that the actual buckling load is less than the compressive load when the car body structure begins to deform plastically.The actual buckling load of the coupler and the asymmetry of the structural strength of the car body in the lateral direction are two important influencing factors for the lateral buckling of a train collision.If the strength of the two sides of the car body structure in the lateral direction is asymmetrical,the deformation on the weaker side will be larger,and the end of the car body will begin to deflect under the action of the coupler force,which in turn causes the train to undergo sawtooth buckling. 展开更多
关键词 Intermediate coupler Rigid-flexible coupling finite element model Design buckling load Actual buckling load Lateral buckling instability
下载PDF
Behaviour of non-ballast pre-stressed and precast track structures in high speed railway based on multiscale finite element model
19
作者 Yuhang Wang Jjun Wang +2 位作者 Qi Tang Jike Tan Guobing Lu 《High-Speed Railway》 2023年第1期70-85,共16页
In order to make further study on the mechanical property of CRTSIII type slab non-ballast track structures,which was self-designed in China,based on the method of the multiscale finite element model(FEM),the traditio... In order to make further study on the mechanical property of CRTSIII type slab non-ballast track structures,which was self-designed in China,based on the method of the multiscale finite element model(FEM),the traditional FEM of slab non-ballast track structures was improved.The multiscale FEM of CRTSII type slab nonballast track structures was established based on the general finite element program ABAQUs.Then the comparative calculation was made between various FEMs,showing that the high solution precision,fast modelling speed and high solution efficiency could be obtained.Therefore,the multiscale FEM was suitable for the parametric study on mechanical behaviour of CRTSII type slab non-ballast track structures,and then the key influence factor and constructions could be optimized. 展开更多
关键词 High speed railway Non-ballast track Multiscale finite element model
下载PDF
A three-dimensional semi-implicit unstructured grid finite volume ocean model 被引量:10
20
作者 WANG Zhili GENG Yanfen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第1期68-78,共11页
A new three-dimensional semi-implicit finite-volume ocean model has been developed for simulating the coastal ocean circulation, which is based on the staggered C-unstructured non-orthogonal grid in the hor- izontal d... A new three-dimensional semi-implicit finite-volume ocean model has been developed for simulating the coastal ocean circulation, which is based on the staggered C-unstructured non-orthogonal grid in the hor- izontal direction and z-level grid in the vertical direction. The three-dimensional model is discretized by the semi-implicit finite-volume method, in that the free-surface and the vertical diffusion are semi-implicit, thereby removing stability limitations associated with the surface gravity wave and vertical diffusion terms. The remaining terms in the momentum equations are discretized explicitly by an integral method. The partial cell method is used for resolving topography, which enables the model to better represent irregular topography. The model has been tested against analytical cases for wind and tidal oscillation circulation, and is applied to simulating the tidal flow in the Bohal Sea. The results are in good agreement both with the analytical solutions and measurement results. 展开更多
关键词 three-dimensional model finite volume unstructured grid SEMI-IMPLICIT z-level grid
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部