Modelling of shallow water jets using smoothed particle hydrodynamics method.

A numerical model based on Smoothed Particle Hydrodynamics (SPH) is developed to investigate shallow water jets propagating into water tanks and open channel flows. An algorithm to treat upstream and downstream boundary conditions for 2D open-channel flows in SPH context (Federico et al., 2010) is extended to model two-phase flows. Here, a suitable set of inflow-jet particles is introduced in order to assign the jet flow characteristics. Different inflow-jet conditions are tested varying the inlet velocity and analyzing the space-time evolution of the flow field. The two-phase model (Grenier et al., 2009) is also coupled to a SPH advective diffusion form (Aristodemo et al., 2010) in order to evaluate the concentration field induced by the jet injection in a water body. Three test cases are simulated with different initial configurations: intake of pollutant above a water tank, upstream a free-surface channel (coflow jet) and at its bottom (crossflow jets). SPH simulations are compared with other numerical approaches and analytical solutions, showing an overall good agreement in terms of evolution of jet trajectory, velocity and concentration field.