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Spectral, hierarchical, and h-type finite elements (FEs) are compared in the context of their application to structural dynamics analysis. The Timoshenko beam, which is the 1-D analog of Mindlin-type shell elements, is used for comparison in eigenvalue and transient-response analyses. A detailed formulation of each method is presented to illustrate clearly their fundamental differences. The principal advantages of spectral FEs over low-order h-type elements are (a) far superior accuracy for a fixed number of model degrees of freedom (DOF) and (b) much higher computational efficiency at a fixed accuracy level. The principal advantages over hierarchical p-type elements are (a) a mass matrix that is inherently diagonal as opposed to full, (b) DOF that pertain directly to nodal displacements and rotations, and (c) more efficient tensor-product factorization. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The unsteady interaction between an incompressible fluid and a deformable elastic structure is analyzed. An implicit numerical method is proposed. At each time step, the stresses at the fluid–structure interface are determined as a solution of an optimization problem. The modal decomposition of the structure equations leads to a problem to be solved with a reduced number of unknowns. The analytic gradient of the cost function was derived. Numerical tests validate the analytic derivative and show the behavior of a two-dimensional Navier–Stokes equations with plate-like model interaction. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Massive parallel computers have become more attractive for advanced numerical simulations since standard libraries for communication and synchronization; for example MPI have facilitated program development. The present paper discusses two parallel explicit time integration methods for wave propagation problems; the central difference method and the explicit version of the P1–P1 discontinuous galerkin (DG) method. Based on the MIMD model, where data decomposition is accomplished by element-based grid partitioning, parallel versions of both algorithms have been implemented, using the same paradigm for inter-process communication. Numerical examples are illustrated and the achieved performance of the algorithms is discussed. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Based on energy functional and with the inclusion of high-order incompatible dynamic displacement modes, a formulation for 3-D finite dynamic element method (DEM) is developed and a new 8-node solid element is derived in this paper. Numerical results exhibit that the present method provides the most economical and efficient solution when compared with the usual FEM and DEM. Copyright © 2000 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In a dynamic unbounded medium–structure interaction analysis in the time domain performed with the substructure method the unit-impulse response function on the structure–medium interface of the unbounded medium is determined. The consistent infinitesimal finite element cell method based solely on the finite element formulation has been developed for compressible elasticity. In this paper the procedure is expanded to the incompressible case. The limit of Poisson's ratio =0·5 is performed analytically. This yields a concentrated mass in the formulation representing the instantaneous response over the entire domain not present in compressible elasticity. The only modification appears in the coefficient matrices of the consistent infinitesimal finite element equation which can be solved with the same numerical algorithm as in the compressible case. Excellent accuracy results also in very complicated inhomogeneous situations. © 1997 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]