Overcoming the limitations of distinct element method for multiscale modeling of materials with multimodal internal structure
- A. Y. Smolin, E.V. Shilko, S. G. Psakhie, S. Schmauder, S.V. Astafurov, V. L. Popov
- Computational Materials Science
- Discrete element method, Distinct element method, Interphase boundary, Many-body interaction, Multimodal internal structure, Multiscale modeling, Simply deformable element
This paper develops an approach to model the deformation and fracture of heterogeneous materials at different scales (including multiscale modeling) within a discrete representation of the medium. Within this approach, molecular dynamics is used for the atomic-scale simulation. The simply deformable distinct element method is applied for simulating at higher length scales. This approach is proposed to be implemented using a general way to derive relations for interaction forces between distinct elements in a many-body approximation similar to that of the embedded atom method. This makes it possible to overcome limitations of the distinct element method which are related to difficulties in implementing complex rheological and fracture models of solids at different length scales. For an adequate description of the mechanical behavior features of materials at the micro- and mesoscales, two kinds of models that consider grain and phase boundaries within the discrete element framework are proposed. Examples are given to illustrate the application of the developed formalism to the study of the mechanical response (including fracture) of materials with multiscale internal structure. The examples show that the simply deformable distinct element method is a correct and efficient tool for analyzing complex problems in solid mechanics (including mechanics of discontinua) at different scales.
Keywords: Multiscale modeling, Discrete element method, Distinct element method, Simply deformable element, Many-body interaction, Multimodal internal structure, Interphase boundary