An efficient numerical approach to modeling the effects of particle shape on rubble-pile dynamics

• DOI: 10.48550/arxiv.2311.11322
• Publication Date: 2023-01-01
• Authors: Julian C. Marohnic; J. V. DeMartini; D. C. Richardson; Yun Zhang; K. J. Walsh
• Keywords: Rubble; Spherical shell; Particle (ecology)

We present an approach for the inclusion of non-spherical constituents in high-resolution N-body discrete element method (DEM) simulations. use aggregates composed bonded spheres to model components. Though may be applied more generally, we detail our implementation existing code pkdgrav. It has long been acknowledged that grains confer additional shear strength and resistance flow when compared with spheres. As a result, expect rubble-pile asteroids will also exhibit these properties behave differently than comparable rubble piles idealized Since spherical particles avoid some significant technical challenges, most DEM gravity codes have used only particles, or confined relatively low resolutions. discuss work gone into improving performance grains, building on pkdgrav's leading-edge computational efficiency among codes. This allows addition shapes while maintaining efficiencies afforded by tree parallelization. test, simulated gravitational collapse 25,000 bodies parallel. In this case, improvements allowed increase speed nearly factor three naive implementation. Without enhancements, large runs components would remain prohibitively expensive. Finally, results several small-scale tests: spinup due YORP effect, tidal encounters, Brazil-nut Effect. all cases, find measurable impact simulation outcomes.