Open Access

ABSTRACT

Comparisons of coupling General Finite Element Techniques with Molecular Dynamics

by M. Macri¹, P. Chung¹

1 Computational and Information Sciences Directorate, US Army Research Laboratory

The International Conference on Computational & Experimental Engineering and Sciences 2008, 7(2), 77-82. https://doi.org/10.3970/icces.2008.007.077

Abstract

In this paper, we compare three interpolation functions in a discretized continuum when used in coupled dynamic atomistic-to-continuum simulations. The focus is on assessing the ability of the discrete continuum model to capture and accurately represent transient effects, namely a travelling longitudinal wave, through both the mixed atomistic-continuum interface and the non-uniform continuum mesh beyond. We specifically examine the differences among Bubnov-Galerkin, partition of unity, and moving least squares finite element methods, which generally fall under the framework of the meshless Petrov-Galerkin Finite Elements, in the continuum part of the multiscale model, where the key technical distinction is in the penalty formulation we presently adopt for matching at the interface. Our study shows that using partition of unity interpolation functions in this context for the continuum produces superior results compared to the other two approaches.

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