Showing papers in "Computer Methods in Applied Mechanics and Engineering in 1993"

TL;DR: A brief overview of stabilized finite element methods and their application to the advection-diffusion equation is given in this paper, along with a discussion of the developments applied to these methods.

TL;DR: Improved three-dimensional tri-linear elements for finite deformation problems are developed based on an assumed enhanced strain methodology which, in the linear regime, incorporates the classical method of incompatible modes as a particular case.

TL;DR: The equivalence between stabilized finite element methods and the standard Galerkin method with bubble functions is established in an abstract framework, and applications to the advective diffusive model and to the Stokes problem are presented, illustrating the potential of the abstract theory introduced here.

TL;DR: In this paper, an accurate and robust stabilization based on the assumed strain method and an operator orthogonal to constant strain fields is presented for an eight-node hexahedral element with uniform reduced integration.

TL;DR: A priori and a posteriori error estimates are proved for a finite element method for linear second order hyperbolic equations based on a space-time finite element discretization with the basis functions being continuous in space and discontinuous in time.

TL;DR: In this article, a foam-like material, with variable density, is used for the evaluation of material properties, and the approach is implemented in a pre-optimizer for optimal shape finding.

TL;DR: In this article, a nonlinear crosswind dissipation method is proposed to avoid the local oscillations that still remain using the streamline-upwind/Petrov-Galerkin formulation for the scalar convection-diffusion equation.

TL;DR: In this article, the authors compared two finite element formulations of compressible Euler equations based on the conservation and entropy variables and showed that the stabilized formulation based on conservation variables gives solutions which are just as good as those obtained with the entropy variables.

TL;DR: In this paper, a new numerical method for prediction of stresses and displacements in thermo-elasto-plastic material is presented, based on the direct solution of the governing equations for thermal energy and momentum balance.

TL;DR: In this paper, a general finite element solution method for the dynamic response sensitivity of inelastic structures is developed, employing a direct differentiation method, the gradient equation of motion is solved without iteration and by taking advantage of the available solution of the response.

TL;DR: The presentation reveals that the convergence analysis for advective-diffusive equations, as applied before to a linearized form of the compressible Navier-Stokes equations, carries over in a straightforward manner to the Stokes problem and to a regression-based version of the incompressibleNavier- Stokes equations.

TL;DR: It is shown that performances comparable with Fortran can be achieved, without sacrificing too much of the qualities of the prototype program: code understandability, code extendability and easy code debugging.

TL;DR: In this paper, the incompressible Navier-Stokes equations are discretized by stabilized finite element methods, which are applicable to various combinations of interpolation functions, including the simplest equal-order linear and bilinear elements.

TL;DR: In this paper, a new finite element formulation has been developed for analysis of heterogeneous media, in which the second phase is randomly dispersed within the matrix, and a tessellation-based mesh generation technique has been introduced to account for the arbitrariness in location, shape and size of second phase.

TL;DR: In this paper, a three-dimensional thermodynamic model is proposed for large deformations of viscoelastic incompressible solids, which leads to a nonlinear variational problem which is approximated in space by mixed finite elements and in time by a first order implicit scheme.

TL;DR: In this paper, a streamline-upwind/Petrov-Galerkin (SUPG) method with a modified SUPG stabilization matrix is used to handle viscous compressible flow problems with moving boundaries and interfaces.

TL;DR: Two projection techniques for computing approximate solutions to linear systems of the form Ax^n=b^n, for a sequence n=1,2,..., e.g., arises from time discretization of a partial differential equation are presented.

TL;DR: In this paper, the authors studied tensile instabilities for an elastic-plastic bar with rectangular cross-section, using a full three-dimensional numerical analysis, based on the simplest flow theory of plasticity, but also the effect of yield surface curvature and the effect on ductile failure mechanisms are considered in a few computations.

TL;DR: In this paper, the problem of parameter uncertainty in random vibrations of structures is addressed as an anti-optimization problem of finding the least favorable values of the mean-square response.

TL;DR: S symmetrization is achieved by a modified multiplier update scheme in which all nonassociativity is removed from the solution phase and placed in the multiplier update phase, resulting in an algorithm involving only the solution of symmetric equations.

TL;DR: In this paper, a theory for material design in a hollow circular cylinder subjected to asymmetric heating on the inner boundary is given for a finite element finite element analysis with full spatial distribution in the volume fraction of the phases.

TL;DR: In this article, an incremental, direct differentiation method for design sensitivity analysis of structures with rate-independent elastoplastic behavior is presented, which can be evaluated with only a modest increase in computational expense beyond the cost of simulation.

TL;DR: In this article, a new quadrilateral element using isoparametric bilinear basis functions for both components of the rotation vector and the deflection is introduced, which is a stable modification of the MITC4 element.

TL;DR: In this paper, two quadrilateral plate elements based on Reissner-Mindlin plate theory and an enhanced displacement interpolation are discussed for the analysis of both thick and thin plates.

TL;DR: In this paper, a model for the behaviour of the contact interface is proposed and combined with the conventional equations of linear thermoelasticity for the bulk material of the contacting bodies.

TL;DR: In this paper, a methodology is presented for thermoelastic material design in functionally gradient materials (FGMs) to reduce the thermo-elastic thermal stresses induced under the would-be operational thermal boundary conditions.

TL;DR: In this paper, the authors developed a methodology to simultaneously treat phenomena at several scales, including a detailed error diagnosis which identifies critical regions, and a feedback procedure which overlays portions of the finite element mesh, where unacceptable errors have been identified, by local finite element meshes(es), and subsequently improves the quality of the solution in the global and local response until the desired level of accuracy is achieved.

TL;DR: The implementation of the method with a penalty contact method is described and it is shown that the method easily and automatically handles edge-to-edge, edge- to-surface, and self-surface contact without any user specification.

TL;DR: The stabilized space-time formulation for moving boundaries and interfaces, and a new stabilized velocity-pressure-stress formulation are both described, and significant aspects of the implementation of these methods on massively parallel architectures are discussed.