摘要:

AbstractFor some heterogeneous materials, it is not practical to model the microstructure directly using traditional finite elements. Furthermore, it is not always accurate to use homogenized properties. Macro elements have been developed which permit microstructure within a single element. These macro elements performed well in initial tests.

ISSN:1069-8299    

DOI:10.1002/cnm.1640091202

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractA procedure was implemented to determine the optimum values for the two parameters of the Zienkiewicz three‐level time schemes which could be utilized for the numerical solution of a system of ordinary differential equations. A multivariable search method was implemented to estimate optimum values for these parameters. The resultant optimum three‐level time scheme produced very accurate results, satisfied physical reality, and did not produce any oscillations for the various problems that were investigated. The optimum values for the two parameters β and γ in the three‐level scheme were β = 0·50005 and γ = 1·0007. A comparison was made between this optimum scheme and other existing three‐level time schemes. The optimum scheme demonstrated superior results for all the problems that were analysed. However, the results of the optimization analysis produced a set of optimum parameters that were identical to the values that would reduce the general three‐level time scheme into a central‐difference two‐level time scheme, i.e

ISSN:1069-8299    

DOI:10.1002/cnm.1640091203

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe paper deals with the solution of the quasi‐harmonic equation by the finite element method in a domain with corners on its boundary. A mapping technique, which can be used for locating the nodes of standard isoparametric elements in a subgrid (patch) of finite elements in the vicinity of a corner singularity point, is presented. The equations of the mapping are based on the analytical singular solution of the problem. Some analytical and numerical results to show the efficiency of the technique are presente

ISSN:1069-8299    

DOI:10.1002/cnm.1640091204

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractAn arbitrary Lagrangian‐Eulerian model is described for the prediction of metal flow in a steady‐state forming process. The formulation is shown to be capable of dealing with free surface and boundary friction; the coupling with thermal effects is also considered. The numerical techniques are based on the finite elements for spatial discretization of the momentum equation and on an explicit integration scheme for discretization relative to time. The mass and energy equations are integrated by a finite‐volume method. Details on the application to an orthogonal cutting process are given in the final Section of the

ISSN:1069-8299    

DOI:10.1002/cnm.1640091205

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractA new efficient formulation of the 36 degree‐of‐freedom conforming shallow shell element of an arbitrary triangular shape is presented. This formulation is based on natural co‐ordinates and independently assumed natural strain fields, and applied to shallow shell analysis. The 3‐node element incorporates the normal displacement and its first and second derivatives plus the tangential displacements and their first derivatives at each vertex. A closed form of the element stiffness matrix is achieved. The form of the stiffness matrix derived in this formulation explicitly reveals the essence of the shallow shell theory.The presented approach results in avoiding definite integrals and matrix inversions, and permits operation with lower‐order numerical matrices, which are the same for all elements. The example applications presented demonstrate that accurate predictions of stresses as well as displacements are obtained with only a few

ISSN:1069-8299    

DOI:10.1002/cnm.1640091206

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe formulation of a straight beam element to eliminate the shear locking phenomenon is presented. The element is based on curvature so that the bending energy is fully represented, and the shear strain energy is incorporated into the formulation by the equilibrium equation. Four examples are chosen to verify the concept of the element employed and its capability of the analysis. The solutions obtained reveal that the element describes the behaviour of the straight beam quite exactly and efficiently, showing no locking and that it is also applicable to the analysis of both thin and thick straight beams.

ISSN:1069-8299    

DOI:10.1002/cnm.1640091207

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

ISSN:1069-8299    

DOI:10.1002/cnm.1640091208

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

ISSN:1069-8299    

DOI:10.1002/cnm.1640091201

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY