Simulation of fines migration using a non-Newtonian lattice Boltzmann-discrete element model Part II: 3D extension and applications

Purpose - The purpose of this paper is to present a novel computational framework based on the lattice Boltzmann method (LBM) and discrete element method (DEM) capable of simulating fines migration in three dimensions. Fines migration occurs in a block cave mine, and is characterised by the faster movement of fine and often low-grade material towards the draw point in comparison to larger, blocky material. Design/methodology/approach - This study builds on the foundations and applications outlined in a companion paper, in which the non-Newtonian LBM-DEM framework is defined and applied in 2D simulations. Issues relevant to the extension to 3D, such as spatial discretisation, fluid boundary conditions and the definition of synthetic bulk material parameters using a power law model, are discussed. Findings - The results of the 3D DEM percolation replication showed that migration is predominantly limited to within the draw zone, and that the use of a low-cohesion material model resulted in a greater amount of fines migration. The draw sensitivity investigation undertaken with the two bell partial block cave analysis did not show a significant difference in the amount of migration, despite the two draw strategies being deliberately chosen to result in isolated and interactive draw of material. Originality/value - Along with the companion paper, this paper presents a novel application of the developed non-Newtonian LBM-DEM framework in the investigation of fines migration, which until now has been limited to scale models, cellular automata or pure DEM simulations. The results highlight the potential for this approach to be applied in an industrial context, and indicate a number of potential avenues for further research.