Description
Surface and volume coupling methods are reformulated for concurrent multi-scale modeling of granular materials. Based on a micro-macro transition technique called “coarse-graining” [1], we derive homogenization operators in more generalized forms than those reported in the literature. For surface coupling [2], coarse graining allows distributing the coupling forces beyond the finite elements that the particles are locally coupled with, namely, from contact points to their neighboring integration points. For volume coupling [3], coarse-graining is applied to enrich the homogenization/localization operations on particle scale quantities, thereby offering a non-local coupling approach. The generalized coupling terms contain one user-defined parameter, namely, the coarse-graining width, setting a length scale for the “coarsegrained” fields. The benefits of coarse-graining in surface and volume coupling are exemplified by modeling particle-cantilever interaction and wave propagation between discrete particles and continuum bodies. We show that the CG-enriched new formulation removes high-frequency/short-wavelength numerical oscillations and gives more physical predictions in the example of particle-cantilever interaction, compared with the conventional formulation using finite element basis functions. In the wave propagation example, the numerical dissipation, which is a known artifact of the volume coupling method, is reduced with an optimal coarse-graining width. In particular, the benefit of coarse-graining appears to be significant when the waveforms become increasingly complex and contain high frequency contents.REFERENCES
[1] Weinhart, T., Hartkamp, R., Thornton, A.R., Luding, S., 2013. Coarse-grained local and objective
continuum description of three-dimensional granular flows down an inclined surface. Phys. Fluids
25, 070605.
[2] Michael, M., Vogel, F., Peters, B., 2015. DEM–FEM coupling simulations of the interactions between
a tire tread and granular terrain. Comput. Methods Appl. Mech. Eng. 289, 227–248.
[3] Wellmann, C., Wriggers, P., 2012. A two-scale model of granular materials. Comput. Methods
Appl. Mech. Eng. 205-208, 46–58.
| Period | 30 Jul 2022 → 5 Aug 2022 |
|---|---|
| Event title | 15th World Congress on Computational Mechanic, WCCM 2022 |
| Event type | Conference |
| Conference number | 15 |
| Location | Yokohama, JapanShow on map |
| Degree of Recognition | International |