Discrete-element model for dynamic fracture of a single particle

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:166

Article

Orozco, Luisa Fernanda^1,2  Delenne, Jean-Yves³  Sornay, Philippe¹  Radjai, Farhang² 

[1] CEA, DEN, DEC, SA3E,LCU, F-13108 St Paul Les Durance, France

[2] Univ Montpellier, LMGC, CNRS, Montpellier, France

[3] Univ Montpellier, IATE, INRA, CIRAD,Montpellier SupAgro, Montpellier, France

关键词: Granular materials;    DEM;    Contact dynamics;    Impact test;    Fracture energy;    Damage;   

DOI  :  10.1016/j.ijsolstr.2019.01.033

来源: Elsevier

【 摘 要 】

We investigate the dynamic fracture of a single particle impacting a flat surface using 3D DEM simulations based on a fragmentation model involving both a stress threshold and a fracture energy. The particle is assumed to be perfectly rigid and discretized into polyhedral Vorondi cells with cohesive interfaces. A cell-cell interface loses its cohesion when it is at a normal or tangential stress threshold and an amount of work equal to the fracture energy is absorbed as a result of the relative cell-cell displacements. Upon impact, the kinetic energy of the particle is partially consumed to fracture cell-cell contacts but also restituted to the fragments or dissipated by inelastic collisions. We analyze the damage and fragmentation efficiency as a function of the impact energy and stress thresholds and their scaling with fracture energy and impact force. In particular, we find that the fragmentation efficiency, defined as the ratio of the consumed fracture energy to the impact energy, is unmonotonic as a function of the impact energy, the highest efficiency occurring for a specific value of the impact energy. (C) 2019 Elsevier Ltd. All rights reserved.

【 授权许可】

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