An anisotropic mesh adaptation strategy for damage and failure in ductile materials

The aim of this paper is to present the ability of an anisotropic adaptive mesh strategy to insure an accurate finite element approach for structural computations, involving ductile damage and failure, with a minimum number of degrees of freedom. Anisotropic mesh adaptation is still a challenging technique in finite element analyses of computational solids, especially for 3D configurations. The proposed h-adaptive strategy is driven by an error indicator based on the interpolation error estimate. This interpolation error estimate allows constructing a metric field, which is then used to generate the anisotropic adapted mesh thanks to the MTC software. Numerical analyses of problems that handle ductile damage and failure can lead to a highly localized structural response of materials, especially in the post critical stage. In order to optimize the mesh with respect to this localization, the employed metric to adapt the mesh is achieved by the proper combination of metrics driven by both the damage and the damage rate variables. Numerical examples, on 2D and on 3D configurations, illustrate the efficiency of the proposed strategy to generate optimal adaptive meshes of ductile damage analyses and crack propagation. Moreover, this mesh adaptation has widely contributed to obtain reliable and physical results, for example, it enables to predict the cup-and-cone profile of ductile fracture for the tensile test of a notched cylindrical specimen.