A coupled 3D discrete elements/isogeometric method for particle/structure interaction problems

To utilize the geometry smoothness of isogeometric analysis for solid media and the effectiveness of the discrete element method for particulate matters, a coupled three-dimensional isogeometric/discrete element method is developed to model the contact interaction between structures and particles. The coupling procedure for handling interactions between isogeometric elements and discrete elements includes global search, local search/resolution and interaction force calculation. Since interaction models for contacting particles and isogeometric elements have significant effects on the contact forces in simulations, several commonly used contact models, including linear, Hertz and quadratic models, are investigated. For a small ball impacting a thick plate example, it is found that the Hertz contact model exhibits the best behavior as the interaction law between a sphere and an isogeometric element in the elastic regime, and no additional correction factor is needed. In addition, an assembly of randomly arranged granular particles impacting a tailor rolled blank is also simulated to further illustrate the applicability of the proposed method.