CIMEC   24726
CENTRO DE INVESTIGACION DE METODOS COMPUTACIONALES
Unidad Ejecutora - UE
artículos
Título:
Elemental Enriched Spaces for the Treatment of Weak and Strong Discontinuous Fields
Autor/es:
JULIO MARTI; SERGIO R. IDELSOHN; NORBERTO M. NIGRO; JUAN M. GIMENEZ
Revista:
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
Editorial:
ELSEVIER SCIENCE SA
Referencias:
Lugar: Amsterdam; Año: 2017 vol. 313 p. 535 - 559
ISSN:
0045-7825
Resumen:
This paper presents a finite element that incorporate weak, strong and both weak plus strong discontinuities withlinear interpolations of the unknown jumps for the modeling of internal interfaces. The new enriched space is builtby subdividing each triangular or tetrahedral element in several standard linear sub-elements. The new degrees offreedom coming from the assembly of the sub-elements can be eliminated by static condensation at the element level,resulting in two main advantages: first, an elemental enrichment instead of a nodal one, which present an importantreduction of the computing time when the internal interface is moving all around the domain and second, an efficientimplementation involving minor modifications allowing to reuse existing finite element codes. The equations for theinternal interface are constructed by imposing the local equilibrium between the stresses in the bulk of the element andthe tractions driving the cohesive law, with the proper equilibrium operators to account for the linear kinematics of thediscontinuity. To improve the continuity of the unknowns on both sides of the elements on which a static condensationis done, a contour integral has been added. These contour integrals named inter-elemental forces can be interpretedas a ?do nothing? boundary condition [1] published in another context, or as the usage of weighting functions thatensure convergence of the approach as proposed by J.C. Simo [2]. A series of numerical tests for scalar unknownsas a simple representation of more general numerical simulations are presented to illustrate the performance of theenriched elemental space.