Simulating free-surface channel flows through SPH,

In this work, a study of 2D open-channel flows has been performed through a SPH solver. An in/out-flow algorithm has been developed to treat this class of hydraulic problems. In order to assign different upstream and downstream flow conditions, two new sets of particles (in/out-flow particles) have been introduced. These boundary particles affect the fluid particles but, on the opposite, are not affected by fluid particles. Two kinds of simulations have been carried out. First, a viscous laminar flow has been considered with Reynolds number of order O(10 2 ). A comparison between the in/out-flow boundary conditions and periodic conditions has been proposed. The simulations are carried on for a time interval long enough to reach a steady state condition. Three different spatial resolutions have been compared with analytical solution in order to heuristically check the convergence of the numerical scheme. As a second test case we studied the hydraulic jump. This represents a strongly dissipative hydrodynamic problem. Different types of jumps, obtained varying the Froude number, are investigated with particular reference to the location of the jump and the velocity field. The model has been validated comparing the numerical water depths with the theoretical ones.