A mesh-free particle model for simulation of flow and sediment transport in open channels

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Solving fluid flow problems numerically may be based on the Eulerian formulation, the Lagrangian method, or a hybrid approach. Due to mesh adaptability and connectivity problems, mesh-based numerical methods such as finite difference, finite element, or finite volume methods have difficulties in the modeling of complicated phenomena with large deformation and fragmentation of geometry and interfaces such as wave breaks and violent river flows. The mesh-free methods use a set of arbitrarily distributed particles instead of mesh to solve governing equations in all kinds of boundaries and interfaces. In particle methods, governing equations are discretized over a set of arbitrarily distributed particles moving in Lagrangian coordination. Each particle possesses a set of field variables such as mass, concentration and momentum. To improve the computational efficiency, the weakly compressible MPS method (WC-MPS) for modeling of incompressible fluids has been developed and showed that this method not only improves the MPS artificial fluctuations, but also increases the model efficiency compared to original MPS. In this research program, MPS method will be employed and expanded to simulated free surface open channel flow, granular flow, and porous flow. The advantage of improving and using particle method is that it can show the transitional and unsteady processes of complicated phenomena such as hydraulic jumps, waves, porous flow, sediment transport, and flow and sediment details during erosion and deposition processes. These phenomena have not been completely simulated using other numerical methods. This research project is to modify the MPS model to study the interface between porous flow and channel flow, including the seepage flow and seepage force near the interface, and expand the developed multiphase flow model to simulate granular flows.