A discrete contact model for complex arbitrary-shaped convex geometries

Abstract

The shape of particles has a significant influence on the behavior of suspensions, as the particle-fluid, particle-particle, and particle-wall interactions depend on it. However, the simultaneous consideration of complex particle shapes and four-way coupling remains a major challenge. This is mainly due to a lack of suitable contact models. Contact models for complex shapes have been proposed in literature, and most limit the accuracy of the particle-fluid interaction. For this reason, this paper presents a novel contact model for complex convex particle shapes for use with partially saturated methods, in which we propose to obtain necessary contact properties, such as the indentation depth, by a discretization of the contact area. The goal of the proposed model is to enable comprehensive and accurate studies of particulate flows, especially with high volume fractions, that lead to new insights and contribute to the improvement of existing industrial processes. To ensure correctness and sustainability, we validate the model extensively by studying cases with and without fluid. In the latter case, we use the homogenized lattice Boltzmann method. The provided investigations show a great agreement of the proposed discrete contact model with analytical solutions and the literature.