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Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils
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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
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A New Classification Method of Stress Modes in Hybrid Stress Finite Element 被引量:1
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作者 韩建新 冯伟 《Advances in Manufacturing》 SCIE CAS 2000年第S1期29-33,共5页
The paper presents a new method for classifying the stress modes in hybrid stress finite element in terms of natural stress modes in finite element and the rank analysis of matrix G in forming element It reveals the r... The paper presents a new method for classifying the stress modes in hybrid stress finite element in terms of natural stress modes in finite element and the rank analysis of matrix G in forming element It reveals the relation among the different assumed stress field, and gives the general method in forming stress field Comparing with the method of eigenvalue analysis, the new method is more efficient 展开更多
关键词 rank of matrix hybrid stress finite element natural stress mode classification
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THE STRESS SUBSPACE OF HYBRID STRESS ELEMENT AND THE DIAGONALIZATION METHOD FOR FLEXIBILITY MATRIX H 被引量:2
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作者 张灿辉 冯伟 黄黔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第11期1263-1273,共11页
The following is proved: 1) The linear independence of assumed stress modes is the necessary and sufficient condition for the nonsingular flexibility matrix; 2) The equivalent assumed stress modes lead to the identica... The following is proved: 1) The linear independence of assumed stress modes is the necessary and sufficient condition for the nonsingular flexibility matrix; 2) The equivalent assumed stress modes lead to the identical hybrid element. The Hilbert stress subspace of the assumed stress modes is established. So, it is easy to derive the equivalent orthogonal normal stress modes by Schmidt's method. Because of the resulting diagonal flexibility matrix, the identical hybrid element is free from the complex matrix inversion so that the hybrid efficiency, is improved greatly. The numerical examples show that the method is effective. 展开更多
关键词 hybrid stress finite element Hilbert stress subspace diagonalization method for flexibility matrix
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ANALYSIS OF AUGMENTED THREE-FIELD MACRO-HYBRID MIXED FINITE ELEMENT SCHEMES 被引量:1
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作者 Gonzalo Alduncin 《Analysis in Theory and Applications》 2009年第3期254-282,共29页
On the basis of composition duality principles, augmented three-field macrohybrid mixed variational problems and finite element schemes are analyzed. The compatibility condition adopted here, for compositional dualiza... On the basis of composition duality principles, augmented three-field macrohybrid mixed variational problems and finite element schemes are analyzed. The compatibility condition adopted here, for compositional dualization, is the coupling operator surjectivity, property that expresses in a general operator sense the Ladysenskaja-Babulka-Brezzi inf-sup condition. Variational macro-hybridization is performed under the assumption of decomposable primal and dual spaces relative to nonoverlapping domain decompositions. Then, through compositional dualization macro-hybrid mixed problems are obtained, with internal boundary dual traces as Lagrange multipliers. Also, "mass" preconditioned aug- mentation of three-field formulations are derived, stabilizing macro-hybrid mixed finite element schemes and rendering possible speed up of rates of convergence. Dual mixed incompressible Darcy flow problems illustrate the theory throughout the paper. 展开更多
关键词 composition duality principle macro-hybrid mixed finite element augmented variational formulation Darcy problem nonoverlapping hybrid domain de composition
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A NEW HYBRID QUADRILATERAL FINITE ELEMENT FOR MINDLIN PLATE
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作者 秦奕 张敬宇 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第2期189-199,共11页
In this paper a new quadrilateral plate element concerning the effect of transverse shear strain has been presented. It is derived from the hybrid finite element model based on the principles of virtual work. The outs... In this paper a new quadrilateral plate element concerning the effect of transverse shear strain has been presented. It is derived from the hybrid finite element model based on the principles of virtual work. The outstanding advantage of this element is to use more rational trial functions of the displacements. For this reason, every variety of plate deformation can be simulated really whilc the least degrees of freedom is employed.A wide range of numerical tests was conducted and the results illustrate that this element has a very wide application scope to the thickness of plates and satisfactory accuracy can be obtained by coarse mesh for all kinds of examples. 展开更多
关键词 hybrid finite element Mindlin plate zero-energy mode eigenvalue test
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Comparison of perfectly matched layer and multi-transmitting formula artificial boundary condition based on hybrid finite element formulation
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作者 李宁 谢礼立 翟长海 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第6期684-695,共12页
The theory of perfectly matched layer (PML) artificial boundary condition (ABC), which is characterized by absorption any wave motions with arbitrary frequency and arbitrarily incident angle, is introduced. The co... The theory of perfectly matched layer (PML) artificial boundary condition (ABC), which is characterized by absorption any wave motions with arbitrary frequency and arbitrarily incident angle, is introduced. The construction process of PML boundary based on elastodynamic partial differential equation (PDE) system is developed. Combining with velocity-stress hybrid finite element formulation, the applicability of PML boundary is investigated and the numerical reflection of PML boundary is estimated. The reflectivity of PML and multi-transmitting formula (MTF) boundary is then compared based on body wave and surface wave simulations. The results show that although PML boundary yields some reflection, its absorption performance is superior to MTF boundary in the numerical simulations of near-fault wave propagation, especially in comer and large angle grazing incidence situations. The PML boundary does not arise any unstable phenomenon and the stability of PML boundary is better than MTF boundary in hybrid finite element method. For a specified problem and analysis tolerance, the computational efficiency of PML boundary is only a little lower than MTF boundary. 展开更多
关键词 perfectly matched layer multi-transmitting formula elastodynamic wave artificial boundary hybrid finite element
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MIXED HYBRID PENALTY FINITE ELEMENT METHOD AND ITS APPLICATION
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作者 梁国平 傅子智 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1984年第3期1345-1357,共13页
The penalty and hybrid methods are being much used in dealing with the general incompatible element, With the penalty method convergence can always be assured, but comparatively speaking its accuracy is lower, and the... The penalty and hybrid methods are being much used in dealing with the general incompatible element, With the penalty method convergence can always be assured, but comparatively speaking its accuracy is lower, and the condition number and sparsity are not so good. With the hybrid method, convergence can be assured only when the rank condition is satisfied. So the construction of the element is extremely limited. This paper presents the mixed hybrid penalty element method, which combines the two methods together. And it is proved theoretically that this new method is convergent, and it has the same accuracy, condition number and sparsity as the compatible element. That is to say, they are optimal to each other.Finally, a new triangle element for plate bending with nine freedom degrees is constructed with this method (three degreesof freedom are given on each corner -- one displacement and tworotations), the calculating formula of the element stiffness matrix is almost the same as that of the old triangle element for plate bending with nine degrees of freedom But it is converged to true solution with arbitrary irregrlar triangle subdivision. If the true solution u?H3 with this method the linear and quadratic rates of convergence are obtianed for three bending moments and for the displacement and two rotations respectively. 展开更多
关键词 MIXED hybrid PENALTY finite element METHOD AND ITS APPLICATION 工工 SO
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INCREMENTAL ANALYSIS FOR NONLINEAR RUBBER-LIKE MATERIALS BY HYBRID STRESS FINITE ELEMENT
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作者 范家齐 杨晓翔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第6期529-537,共9页
In this paper, on the basis of the incremental Reissner variational principle.a nonlinear finite element analysis has been accomplished and a formulation of hybrid stress element has been presented for incompressible ... In this paper, on the basis of the incremental Reissner variational principle.a nonlinear finite element analysis has been accomplished and a formulation of hybrid stress element has been presented for incompressible Mooney rubber-like materials. The corrected terms of the non-equilibrium force and the incompressibility deviation are considered in the formulation. The computed values of numerical example agree very closely with the exact solution. 展开更多
关键词 INCREMENTAL ANALYSIS FOR NONLINEAR RUBBER-LIKE MATERIALS BY hybrid STRESS finite element
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Damage prediction for magnesium matrix composites formed by liquid-solid extrusion process based on finite element simulation 被引量:6
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作者 齐乐华 刘健 +2 位作者 关俊涛 苏力争 周计明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1737-1742,共6页
A damage prediction method based on FE simulation was proposed to predict the occurrence of hot shortness crocks and surface cracks in liquid-solid extrusion process. This method integrated the critical temperature cr... A damage prediction method based on FE simulation was proposed to predict the occurrence of hot shortness crocks and surface cracks in liquid-solid extrusion process. This method integrated the critical temperature criterion and Cockcroft & Latham ductile damage model, which were used to predict the initiation of hot shortness cracks and surface cracks of products, respectively. A coupling simulation of deformation with heat transfer as well as ductile damage was carried out to investigate the effect of extrusion temperature and extrusion speed on the damage behavior of Csf/AZ91D composites. It is concluded that the semisolid zone moves gradually toward deformation zone with the punch descending. The amplitude of the temperature rise at the exit of die from the initial billet temperature increases with the increase of extrusion speed during steady-state extrusion at a given punch displacement. In order to prevent the surface temperature of products beyond the incipient melting temperature of composites, the critical extrusion speed is decreased with the increase of extrusion temperature, otherwise the hot shortness cracks will occur. The maximum damage values increase with increasing extrusion speed or extrusion temperature. Theoretical results obtained by the Deform^TM-2D simulation agree well with the experiments. 展开更多
关键词 magnesium matrix composite liquid-solid extrusion hot shortness cracks surface cracks finite element method
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Multiscale Hybrid-Mixed Finite Element Method for Flow Simulation in Fractured Porous Media 被引量:2
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作者 Philippe Devloo Wenchao Teng Chen-Song Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第4期145-163,共19页
The multiscale hybrid-mixed(MHM)method is applied to the numerical approximation of two-dimensional matrix fluid flow in porous media with fractures.The two-dimensional fluid flow in the reservoir and the one-dimensio... The multiscale hybrid-mixed(MHM)method is applied to the numerical approximation of two-dimensional matrix fluid flow in porous media with fractures.The two-dimensional fluid flow in the reservoir and the one-dimensional flow in the discrete fractures are approximated using mixed finite elements.The coupling of the two-dimensional matrix flow with the one-dimensional fracture flow is enforced using the pressure of the one-dimensional flow as a Lagrange multiplier to express the conservation of fluid transfer between the fracture flow and the divergence of the one-dimensional fracture flux.A zero-dimensional pressure(point element)is used to express conservation of mass where fractures intersect.The issuing simulation is then reduced using the MHM method leading to accurate results with a very reduced number of global equations.A general system was developed where fracture geometries and conductivities are specified in an input file and meshes are generated using the public domain mesh generator GMsh.Several test cases illustrate the effectiveness of the proposed approach by comparing the multiscale results with direct simulations. 展开更多
关键词 FRACTURE simulation DISCRETE FRACTURE model multiscale hybrid finite element mixed FORMULATION
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COARSE-MESH-ACCURACY IMPROVEMENT OF BILINEAR Q_4-PLANE ELEMENT BY THE COMBINED HYBRID FINITE ELEMENT METHOD 被引量:1
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作者 谢小平 周天孝 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第12期1456-1465,共10页
The combined hybrid finite element method is of an intrinsic mechanism of enhancing coarse-mesh-accuracy of lower order displacement schemes. It was confirmed that the combined hybrid scheme without energy error leads... The combined hybrid finite element method is of an intrinsic mechanism of enhancing coarse-mesh-accuracy of lower order displacement schemes. It was confirmed that the combined hybrid scheme without energy error leads to enhancement of accuracy at coarse meshes, and that the combination parameter plays an important role in the enhancement. As an improvement of conforming bilinear Q(4)-plane element, the combined hybrid method adopted the most convenient quadrilateral displacements-stress mode, i.e.,the mode of compatible isoparametric bilinear displacements and pure constant stresses. By adjusting the combined parameter, the optimized version of the combined hybrid element was obtained and numerical tests indicated that this parameter-adjusted version behaves much better than Q(4)-element and is of high accuracy at coarse meshes. Due to elimination of stress parameters at the elemental level, this combined hybrid version is of the same computational cost as that of Q(4)-element. 展开更多
关键词 finite element hybrid method zero energy-error coarse-mesh-accuracy
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A HYBRID FINITE ELEMENT SCHEME FOR INVISCID SUPERSONIC FLOWS
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作者 徐守栋 吴望一 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第8期739-748,共10页
A hybrid monotonous finite element algorithm is developed in the present paper, based on a second-order-accurate finite element scheme and a first-accurate monotonous one derived from the former by a unilateral lumpin... A hybrid monotonous finite element algorithm is developed in the present paper, based on a second-order-accurate finite element scheme and a first-accurate monotonous one derived from the former by a unilateral lumping procedure in one dimensional case. The switch functions for the two dimensional Euler equation system are constructed locally, based on the gradient of the flow field, with special consideration on the information from neighboring elements. Examples show that the new scheme can eliminate oscillations near strong shocks obviously. 展开更多
关键词 finite element hybrid scheme SHOCKS
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CHEBYSHEV PSEUDOSPECTRAL-HYBRID FINITE ELEMENT METHOD FOR THREE-DIMENSIONAL VORTICITY EQUATION
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作者 郭本瑜 候镜宇 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1996年第2期161-196,共36页
In this paper,Chebyshev pseudospectral-finite element schemes are proposed for solving three dimensional vorticity equation.Some approximation results in nonisotropic Sobolev spaces are given.The generalized stability... In this paper,Chebyshev pseudospectral-finite element schemes are proposed for solving three dimensional vorticity equation.Some approximation results in nonisotropic Sobolev spaces are given.The generalized stability and the convergence are proved strictly.The numerical results show the advantages of this method.The technique in this paper is also applicable to other three-dimensional nonlinear problems in fluid dynamics. 展开更多
关键词 THREE-DIMENSIONAL VORTICITY EQUATION CHEBYSHEV pseudospectral-hybrid finite element
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Finite element model for arch bridge vibration dynamics considering effect of suspender length adjustment on geometry stiffness matrix
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作者 钟轶峰 《Journal of Chongqing University》 CAS 2006年第4期218-222,共5页
In this paper, we established a finite element (FEM) model to analyze the dynamic characteristics of arch bridges. In this model, the effects of adjustment to the length of a suspender on its geometry stiffness matrix... In this paper, we established a finite element (FEM) model to analyze the dynamic characteristics of arch bridges. In this model, the effects of adjustment to the length of a suspender on its geometry stiffness matrix are stressed. The FEM equations of mechanics characteristics, natural frequency and main mode are set up based on the first order matrix perturbation theory. Applicantion of the proposed model to analyze a real arch bridge proved the improvement in the simulation precision of dynamical characteristics of the arch bridge by considering the effects of suspender length variation. 展开更多
关键词 finite element model SUSPENDER geometry stiffness matrix dynamic characteristic arch bridge
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THE DYNAMIC STIFFNESS MATRIX OF THE FINITE ANNULAR PLATE ELEMENT
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作者 张益松 高德平 吴晓萍 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第12期1151-1162,共12页
The dynamic deformation of harmonic vibration is used as the shape functions of the finite annular plate element, and sonic integration difficulties related to the Bessel's functions are solved in this paper. Then... The dynamic deformation of harmonic vibration is used as the shape functions of the finite annular plate element, and sonic integration difficulties related to the Bessel's functions are solved in this paper. Then the dynamic stiffness matrix of the finite annular plate element is established in closed form and checked by the direct stiffness method. The paper has given wide convcrage for decomposing the dynamic matrix into the power series of frequency square. By utilizing the axial symmetry of annular elements, the modes with different numbers of nodal diameters at s separately treated. Thus some terse and complete results are obtained as the foundation of structural characteristic analysis and dynamic response compulation. 展开更多
关键词 DE THE DYNAMIC STIFFNESS matrix OF THE finite ANNULAR PLATE element PING
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Finite Element Analysis of Push-Out Test of SiC Fiber Reinforced Titanium Matrix Composites 被引量:1
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作者 Yuan M N Yang Y Q Huang B Zhang R J 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2009年第A03期50-53,共4页
Based on the interphase layer model and the spring layer model, an improved interface model was developed to evaluate the interfacial shear strength of Titanium matrix composites(TMCs) and to analyze the effects of va... Based on the interphase layer model and the spring layer model, an improved interface model was developed to evaluate the interfacial shear strength of Titanium matrix composites(TMCs) and to analyze the effects of various parameters on the interfacial properties. The results showed that the improved interface model is more suitable for calculating the interfacial properties of SiC fiber reinforced titanium matrix composites. The interfacial shear strength of SiC/Timetal-834 predicted is 500 MPa. In addition, in order to better understand the interfacial properties of composites, some push out phenomenon were analyzed. 展开更多
关键词 复合材料 剪切强度 碳化硅纤维 物理性能
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Radiation heat transfer model for complex superalloy turbine blade in directional solidification process based on finite element method 被引量:4
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作者 Dun-ming Liao Liu Cao +4 位作者 Tao Chen Fei Sun Yong-zhen Jia Zi-hao Teng Yu-long Tang 《China Foundry》 SCIE 2016年第2期123-132,共10页
For the sake of a more accurate shell boundary and calculation of radiation heat transfer in the Directional Solidification(DS) process, a radiation heat transfer model based on the Finite Element Method(FEM)is develo... For the sake of a more accurate shell boundary and calculation of radiation heat transfer in the Directional Solidification(DS) process, a radiation heat transfer model based on the Finite Element Method(FEM)is developed in this study. Key technologies, such as distinguishing boundaries automatically, local matrix and lumped heat capacity matrix, are also stated. In order to analyze the effect of withdrawing rate on DS process,the solidification processes of a complex superalloy turbine blade in the High Rate Solidification(HRS) process with different withdrawing rates are simulated; and by comparing the simulation results, it is found that the most suitable withdrawing rate is determined to be 5.0 mm·min^(-1). Finally, the accuracy and reliability of the radiation heat transfer model are verified, because of the accordance of simulation results with practical process. 展开更多
关键词 directional solidification radiation heat transfer finite element method numerical simulation local matrix superalloy turbine blade
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The Finite Element Solutions to the Semiconductor Equations
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作者 管平 王文胜 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期75-80,共6页
In this paper, the approximation of stationary equations of the semiconductor devices with mixed boundary conditions is considered. Two schemes are proposed for the system. One is Glerkin discrete scheme, the other is... In this paper, the approximation of stationary equations of the semiconductor devices with mixed boundary conditions is considered. Two schemes are proposed for the system. One is Glerkin discrete scheme, the other is hybrid variable discrete scheme. A convergence analysis is also given. 展开更多
关键词 semiconductor equations finite element Galerkin method hybrid variable method
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A hybridized weak Galerkin finite element scheme for the Stokes equations 被引量:10
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作者 ZHAI QiLong ZHANG Ran WANG XiaoShen 《Science China Mathematics》 SCIE CSCD 2015年第11期2455-2472,共18页
In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivati... In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivatives which are defined as distributions.Weak functions and weak derivatives can be approximated by piecewise polynomials with various degrees.Different combination of polynomial spaces leads to different WG finite element methods,which makes WG methods highly flexible and efficient in practical computation.A Lagrange multiplier is introduced to provide a numerical approximation for certain derivatives of the exact solution.With this new feature,the HWG method can be used to deal with jumps of the functions and their flux easily.Optimal order error estimates are established for the corresponding HWG finite element approximations for both primal variables and the Lagrange multiplier.A Schur complement formulation of the HWG method is derived for implementation purpose.The validity of the theoretical results is demonstrated in numerical tests. 展开更多
关键词 hybridized weak Galerkin finite element methods weak gradient weak divergence Stokes equation
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A COMBINED HYBRID FINITE ELEMENT METHOD FOR PLATE BENDING PROBLEMS 被引量:7
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作者 Tian-xiaoZhou Xiao-pingXie 《Journal of Computational Mathematics》 SCIE CSCD 2003年第3期347-356,共10页
In this paper, a combined hybrid method is applied to finite element discretization of plate bending problems. It is shown that the resultant schemes are stabilized, i.e., the convergence of the schemes is independent... In this paper, a combined hybrid method is applied to finite element discretization of plate bending problems. It is shown that the resultant schemes are stabilized, i.e., the convergence of the schemes is independent of inf-sup conditions and any other patch test. Based on this, two new series of plate elements are proposed. 展开更多
关键词 Combined hybrid finite element Weakly compatible.
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