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arXiv · 1410.2866

An atomistic/continuum coupling method using enriched bases

Jingrun Chen·Carlos J. García-Cervera·Xiantao Li
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Abstract

A common observation from an atomistic to continuum coupling method is that the error is often generated and concentrated near the interface, where the two models are combined. In this paper, a new method is proposed to suppress the error at the interface, and as a consequence, the overall accuracy is improved. The method is motivated by formulating the molecular mechanics model as a two-stage minimization problem. In particular, it is demonstrated that the error at the interface can be considerably reduced when new basis functions are introduced in a Galerkin projection formalism. The improvement of the accuracy is illustrated by two examples. Further, the comparison to some quasicontinuum-type methods is provided.

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Jingrun Chen, Carlos J. García-Cervera, Xiantao Li. 2014-10-10. An atomistic/continuum coupling method using enriched bases. https://arxiv.org/abs/1410.2866

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