A coupled, two-phase fluid-sediment material model and mixture theory implemented using the material point method

Dynamic fluid-sediment interactions present a challenge to traditional numerical modelling techniques. These flows can involve bulk motion of millions of sediment particles (e.g. riverbed and shoreline erosion) and therefore require intensive computational resources for modeling using discrete element methods (DEM). Other flows of interest have highly turbulent regions (e.g. the head of submerged slope avalanches) and are therefore difficult to capture in finite element methods (FEM). Recent work on modeling granular materials as continuum using the material point method (MPM) has shown promise for capturing such complex material dynamics.
A numerical implementation of a new fluid-grain coupled material model in MPM is presented. Qualitative results show the breadth of problems which this model can address. Quantitative results demonstrate the accuracy of this model as compared with analytical models, results of other numerical techniques, and empirical observations.