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Standard finite element formulation and implementation in solid dynamics at large strains usually relies upon and indicial-tensor Voigt notation to factorized the weighting functions and take advantage of the symmetric structure of the algebraic objects involved. In the present work, a novel component-free approach, where no reference to a basis, axes or components is made, implied or required, is adopted for the finite element formulation. Under this approach, the factorisation of the weighting function and also of the increment of the displacement field, can be performed by means of component-free operations avoiding both the use of any index notation and the subsequent reorganisation in matrix Voigt form. This new approach leads to a straightforward implementation of the formulation where only vectors and second order tensors in R 3 are required. The proposed formulation is as accurate as the standard Voigt based finite element method however is more efficient, concise, transparent and easy to implement. [ABSTRACT FROM AUTHOR]

A finite element procedure is proposed for wave propagation in elastic media. The method is based on an alternative formulation for the equations of motion that can systematically be constructed for linear evolutionary partial differential equations. A weak formulation—corresponding to convolutional variational principles—is then defined, which paves the way for introducing a particular type of time-wise shape functions. Next, some mathematical characteristics of the method are investigated, and upon those properties, a new solution procedure for elastodynamics problems is proposed. Subsequently, several numerical examples are considered, including a single degree of freedom mass-spring-damper system as the prototype of structural dynamics along with 1d and 2d elastodynamics problems for the case of the wave motion in elastic solids. The present method can be considered as an alternative approach for time integration and time-marching algorithms, e.g., Newmark's algorithm, to solve time-domain problems in elastic media. [ABSTRACT FROM AUTHOR]

This paper presents an extended/generalized finite element method for bridging scales in linear elastodynamics in the absence of scale separation. More precisely, the GFEMgl framework is expanded to enable the numerical solution of multiscale problems through the automated construction of specially-tailored shape functions, thereby enabling high-fidelity finite element modeling on simple, fixed finite element meshes. This introduces time-dependencies in the shape functions in that they are subject to continuous adaptation with time. The temporal aspects of the formulation are investigated by considering the Newmark- β time integration scheme, and the efficacy of mass lumping strategies is explored in an explicit time-stepping scheme. This method is demonstrated on representative wave propagation examples as well as a dynamic fracture problem to assess its accuracy and flexibility. [ABSTRACT FROM AUTHOR]

In electromechanical devices, a strong coupling exists between the electromagnetic and displacement field. Due to this strong interaction, a need arises to develop a robust, fully coupled scheme for modeling electromechanical phenomena. With this goal in view, we present a monolithic numerical scheme for modeling fully coupled electromechanical systems. It is shown in the literature that for structural problems, hybrid elements that are based on a two-field variational formulation are less susceptible to locking and provide a robust numerical strategy especially for shell-type structures. Hence, we extend our monolithic formulation to the hybrid finite element framework. Our monolithic formulation is based on a total Lagrangian framework, where the eddy current and structural equations are solved on the reference configuration. Consistent linearization is performed to ensure a quadratic rate of convergence. The efficacy of the presented algorithm, and especially that of the hybrid formulation is demonstrated with the help of numerical examples. [ABSTRACT FROM AUTHOR]