A Riemann-based SPH method for modelling large deformation of granular materials

A new smoothed particle hydrodynamic (SPH) method is developed based on a low-dissipation Riemann solver to model the large deformation of granular materials with reduced numerical dissipation to improve the calculation accuracy. Numerical dissipation can be controlled precisely by the limiter in the Riemann solver and a stress diffusion term is adopted to remove the spurious stress profile. The design of our algorithm framework can be applied for both two-dimensional (2D) and three-dimensional (3D) scenarios, and 2D/3D simulations for granular flows are conducted for validation. The numerical results from this study are compared with experimental data from both qualitative and quantitative perspectives, demonstrating a satisfactory agreement and convergence with experimental results. Furthermore, its application on granular flows interactions with rigid barriers and natural terrain is explored and computational efficiency is also investigated. The proposed algorithm is implemented in an open-source library for further comparison and in-depth study.