Showing papers in "Computer Methods in Applied Mechanics and Engineering in 1984"

TL;DR: A survey of finite element methods for convectiondiffusion problems and first-order linear hyperbolic problems can be found in this article, where the authors give a survey of some recent work by the authors.

TL;DR: In this article, a finite element formulation and algorithm for the nonlinear analysis of the large deflection, materially nonlinear response of impulsively loaded shells is presented, which can treat about 200 element-time-steps per CPU second on a CYBER 170/730 computer in the explicit time integration mode.

TL;DR: In this article, the shape optimal design of an elastic structure is formulated using a design element technique, where Bezier and B-spline curves, typical of the CAD philosophy, are well suited to the definition of design elements.

TL;DR: In this paper, a mesh stabilization technique for controlling the hourglass modes in under-integrated hexahedral and quadrilateral elements is described, based on simple requirements that insure the consistency of the finite element equations in the sense that the gradients of linear fields are evaluated correctly.

TL;DR: In this paper, a Petrov-Galerkin finite element formulation for first-order hyperbolic systems of conservation laws with particular emphasis on the compressible Euler equations is presented.

TL;DR: In this article, it was shown that if the elasticity tensor of an elastic material is taken as isotropic for all possible configurations, then its coefficients cannot be constants; they must depend nontrivially on the Jacobian determinant of the deformation gradient.

TL;DR: In this article, a sequential implicit time-stepping procedure is defined, in which the pressure and Darcy velocity of the mixture are approximated simultaneously by a mixed finite element method and the concentration is approximated by a combination of a Galerkin finite element and the method of characteristics.

TL;DR: The perturbation method and the continuation method are the two most popular techniques for the solution of finite element equations that describe instability phenomena as discussed by the authors. But these methods are not suitable for all problems.

TL;DR: In this paper, the authors explore the analysis of the geometrically nonlinear behavior of space structures, using the modified arc length method of Riks and Crisfield, which is robust and able to handle problems that exhibit several negative eigenvalues simultaneously.

TL;DR: The Taylor-Galerkin method is employed to derive accurate and efficient numerical schemes for the solution of time-dependent advection-diffusion problems and is successively extended to deal with nonlinear and multi-dimensional problems.

TL;DR: In this paper, it was shown that the occurrence of such an "anomaly" is not restricted to anisotropic plasticity, but also in the case of hypoelasticity and classical isotropic hardening plasticity theory.

TL;DR: In this paper, the point-wise state variable constraints are replaced by several constraints that are imposed at all the local max-points for the original constraint function, and the differential equations of motion are formulated in the first-order form.

TL;DR: In this article, the least-order stable invariant stress polynomials can be applied as astute approximations in distorted cases through a variety of tensor components and variational principles.

TL;DR: New self-adaptive finite element methods for the numerical analysis of transient flow problems with moving boundaries are presented and use of both h-refinement and p-enrichment methods to enhance the local accuracy of the finite element approximation.

TL;DR: In this article, a space-time least-square finite element scheme is presented for the advection-diffusion problems at moderate to high Peclet numbers, which can be used to define the steady-state solution as the asymptotic transient solution for large time.

TL;DR: In this paper, a new mixed kinematic description for large deformation solid mechanics is presented, where both the initial and current configurations are treated as unknown, and large-deformation statements of the principles of virtual work and stationary potential energy are formulated with the new description and presented in incremental form.

TL;DR: In this paper, an alternative to the Riks-Wempner-Crisfield iterative correction scheme is presented that does not require an explicit displacement-load accession path to the nonlinear equilibrium curve, nor a known equilibrium point.

TL;DR: In this article, the behavior of two-phase flow in a periodically fractured porous medium is studied. But the authors focus on the homogenization of the porosity and the permeability of the medium.

TL;DR: In this paper, a review and analysis of superplastic deformation processes is presented, based on the homogeneous natural definition of stress and rate of deformation, and the numerical characteristics of the proposed techniques are demonstrated.

TL;DR: A ‘modified equation’ analysis is used to characterize grid-dependent anisotropies in the discretization and motivates a new family of finite difference schemes that show essentially no dependence on the orientation of the grid.

TL;DR: In this article, the authors considered the finite deformation, elasto-viscoplastic response of beams from a numerical point of view, and extended the formulation in terms of stress resultants to include viscoplastic material response by introducing rate equations for the evolution of the finite inelastic deformations.

TL;DR: In this article, a procedure that introduces additional generalized stresses and strains so that the spurious singular modes are eliminated and the consistency of the resulting finite difference equations is not impaired is presented.

TL;DR: In this article, variable mesh difference methods of third order are derived for the solution of the two-point, second-order, singular perturbation problems y = f (x, y, y, e ).

TL;DR: In this article, the authors describe the theoretical formulation and computational implementation of a method for treating hull cavitation in underwater-shock problems, which can be applied to the analysis of submerged structures that contain internal fluid volumes.

TL;DR: In so-called primitive variable formulations of problems of flow of viscous, incompressible, Stokesian fluids, two fields appear as unknowns: the velocity field u and the pressure field p, the latter representing a Lagrange multiplier associated with the incompressibility constraint, div u = 0.

TL;DR: In this paper, the numerical integration of a function over tetrahedronal regions is described in the form of quadrature formulae of degrees 2 to 6, which are of Gaussian type and fully symmetric with respect to the four vertices of the tetrahedral structure.

TL;DR: In this paper, a penalty formulation of the stationary Navier-Stokes equations for an incompressible fluid is presented, subject to restrictions on the viscosity and prescribed body force, and it is shown that there exists a unique solution to this penalty problem.

TL;DR: In this article, the authors showed that the finite difference method with arbitrary irregular meshes for some class of elliptic problems converges linearly with the size of the star and confirmed the correctness of this theorem by numerical tests.