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DOE OSTI · 1760571

A smooth contact algorithm for the combined finite discrete element method

Lei, Zhou·Rougier, Esteban·Euser, Bryan Jeffry·Munjiza, Antonio
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Abstract

From its inception, the combined finite discrete element method has used a distributed potential contact force algorithm to resolve interaction between finite elements. The contact interaction algorithm relies on evaluation of the contact force potential field. The problem with existing algorithms is that the potential field introduces artificial numerical non-smoothness in the contact force. This work introduces a smooth potential field based on the finite element topology, and a generalized contact interaction law is constructed on top of the smooth potential field. Further, a number of validation cases for the proposed algorithm, considering different shapes of discrete elements, are presented, and detailed aspects of the proposed contact interaction law are tested with numerical examples.

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97 MATHEMATICS AND COMPUTINGcombined finite-discrete element methodcontact interactioncontact potential fielddiscrete elementearth Sciencesfinite elementmathematics

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Lei, Zhou, Rougier, Esteban, Euser, Bryan Jeffry, Munjiza, Antonio. 2020-03-12. A smooth contact algorithm for the combined finite discrete element method. https://doi.org/10.1007/s40571-020-00329-2

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