Showing papers in "Computer Methods in Applied Mechanics and Engineering in 1992"

TL;DR: A very much improved recovery process yielding superconvergent values throughout the domain, named the superconversgent patch recovery, is presented with test results showing its efficiency.

TL;DR: In this article, a relation between stabilized finite element methods and the Galerkin method employing interpolations with bubble functions is established for the advective-diffusive model and for the linearized compressible Navier-Stokes equations.

TL;DR: In this article, a general approach to adaptivity for finite element methods is presented and applications to linear elasticity, non-linear elasto-plasticity and nonlinear conservation laws, including numerical results.

TL;DR: Results show that the approach is applicable to general linearly elliptic systems, including unsymmetrical operators, and that the method is valid for broad classes of linear and non-linear problems.

TL;DR: The detailed numerical computations show various basic aspects of plate modeling in a concrete setting, including the boundary layer and corner singularities of the solution.

TL;DR: An introduction to time-accurate finite element methods recently developed for solving unsteady problems governed by linear and nonlinear advection equations is presented.

TL;DR: A method which uses an h - p -approximation for a domain decomposition with fully overlapping domains, allowing C 0 -continuous approximation for geometrically incompatible mesh refinement to be obtained is presented.

TL;DR: In this article, a simplified 3D model problem reduced from the general class of elastic scattering problems is analyzed, focusing on such practical details of the 3D implementation as a triangles-based h-p approximation and corresponding data structure, integration of singular integrals and its effect on (theoretically) optimal rates of convergence, a posteriori error estimation and sample adaptive strategies.

TL;DR: In this paper, the reliability and efficiency of automatic 3D mesh generators are considered. But the authors focus on the use of topological adjacency information to improve the reliability of a meshing process.

TL;DR: An improvement in accelerated conjugate gradient iterations is presented for the evaluation of several of the leftmost eigenpairs of large sparse symmetric positive definite matrices and is compared with the accelerated simultaneous iterations performed over large finite element problems.

TL;DR: An automatic, adaptive remeshing scheme with a new, independent mesh has been developed to enable finite element simulations of forming processes with complicated die geometries and this work focuses on the fully automatic aspect of the procedure.

TL;DR: A sequence of nested time-integration methods for dynamic problems formulated as two first order equations in time based on a hierarchical formulation in time are described, a considerable improvement in terms of accuracy as well as effectiveness is obtained.

TL;DR: Experimental rates of convergence for the h version of the symmetric coupling method are presented, where the accuracy of the Galerkin approximation is achieved by refining the mesh.

TL;DR: In this paper, a new plate bending element with shape functions of the Allman-type is presented and used for linear and non-linear problems, and different a posteriori criteria for adaptive approximations are given, such as a gradient-based error with one and two indicators for geometrically nonlinear load paths, the first being residuum based and the second controlling the geometrical nonlinearities.

TL;DR: The present study shows that domain decomposition is better in the nonlinear case, at least as far as coarse grain parallelism and computational efficiency are concerned.

TL;DR: Nonlinear discontinuity-capturing operators are presented that result in more accurate capturing of wave fronts in transient solutions while maintaining the high-order accuracy of the underlying linear algorithm in smooth regions.

TL;DR: Various interpolation methods which are used for the correct space localization of the adaption, for cell center/cell vertex recovery and for overlapping grids interpolation are studied.

TL;DR: This paper analyzes in detail an a posteriori estimator for linear elements on triangular meshes and gives the bounds of the effectivity index depending on the geometry of the triangles and smoothness of the approximated solution.

TL;DR: The adaptive grid method implemented in the 3D general geometry CFD code TRANAIR is described and many computational comparisons are presented to explain the reasoning behind the local error indicator and gridding strategy used.

TL;DR: The need for flexible data structures and solution algorithms to accommodate moving patch refinement to follow moving sharp fronts in fluid flow applications is discussed, and local time-stepping methods are presented to treat transient phenomena.

TL;DR: A variational inequality formulation in strain space is derived for certain problems of flow theory elasto-plastic deformation with hardening as discussed by the authors, and an algorithm is given for implementing a finite element approximation to the variational inequalities formulation.

TL;DR: All three adaptivity techniques significantly improve the accuracy with which flow features, such as shock waves and viscous boundary layers are captured, in two-dimensional structured multiblock meshes.

TL;DR: In this article, a variational approach given by Hamdi reduces this hypersingularity/Cauchy singularity to a weak singularity allowing for its accurate numerical approximation, and a novel solution to the numerical approximation of this operator is given.

TL;DR: In this paper, the authors investigated various sample extremum (saddle point and minimization) problems from the point of view of stability of increasing order mixed finite element methods, including the Stokes, Poisson and linear elasticity problems.

TL;DR: In this article, an adaptive algorithm is given for the bending of viscoelastic beams and plates resting on frictionless foundations, and an a posteriori error indicator is obtained by making use of upper and lower bounds generated by the saddle functional being a potential for the system of equations and inequalities which govern the contact problem.

TL;DR: In this article, the mathematical modeling of coupled plates and its finite element approximations was investigated, and the approach proposed by Feng Kang and Shi Zhong-ci was investigated.

TL;DR: In this paper, the authors studied the robustness properties of the Reissner-Mindlin model for high-order finite elements with respect to the thickness of the plate and the transverse shear strain effect.

TL;DR: A method for adaptive construction of nearly optimal finite element meshes is presented, based on the notion of mesh density, for parametrized problems, where optimal meshes for new parameter values can be predicted from previous meshes.