Multiphase Mesh-Free Particle Method for Simulating Granular Flows and Sediment Transport

The objective of this paper is to develop a straightforward, robust, stable, and accurate mesh-free numerical technique for modeling the dynamic behavior of free surface, incompressible, multiphase granular flows. This method (henceforth, the multiphase MPS method) is based on the fully Lagrangian method of moving particle semi-implicit (MPS). MPS provides approximations to the strong form of PDEs on the basis of integral interpolants. The fluid is represented with particles, and the motion of each particle is calculated based on the interactions with neighboring particles by means of a kernel function. In the proposed multiphase MPS method, a single set of governing equations is solved on the whole computational domain. Density and viscosity smoothening schemes are applied to the phase interfaces to ensure shear stress continuity and stability of the pressure field. The multiphase MPS method is then applied to model deformable submarine landslide and dam-break over an erodible bed. It is assumed that the granular media is behaving as a non-Newtonian fluid. The simulated water and sediment surface profiles accurately match the available experimental data. This proves the applicability and accuracy of the proposed multiphase MPS method for modeling similar environmental granular flows.