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arXiv · 2108.02336

A Fracture Multiscale Model for Peridynamic enrichment within the Partition of Unity Method

Matthias Birner·Patrick Diehl·Robert Lipton·Marc Alexander Schweitzer
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Abstract

Partition of unity methods (PUM) are of domain decomposition type and provide the opportunity for multiscale and multiphysics numerical modeling. Different physical models can exist within a PUM scheme for handling problems with zones of linear elasticity and zones where fractures occur. Here, the peridynamic (PD) model is used in regions of fracture and smooth PUM is used in the surrounding linear elastic media. The method is a so-called global-local enrichment strategy. The elastic fields of the undamaged media provide appropriate boundary data for the localized PD simulations. The first steps for a combined PD/PUM simulator are presented. In part I of this series, we show that the local PD approximation can be utilized to enrich the global PUM approximation to capture the true material response with high accuracy efficiently. Test problems are provided demonstrating the validity and potential of this numerical approach.

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Matthias Birner, Patrick Diehl, Robert Lipton, Marc Alexander Schweitzer. 2023-02-03. A Fracture Multiscale Model for Peridynamic enrichment within the Partition of Unity Method. https://doi.org/10.1016/j.advengsoft.2022.103360

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