A hybrid solid boundary treatment algorithm for smoothed particle hydrodynamics

This study presents a new hybrid algorithm for treating solid walls in the context of a weakly-compressible SPH model. The basic concept is to ll an impervious region with some layers of dummy particles for improving the solution accuracy, and a single layer of repulsive particles to impose a no-penetration condition along the solid- uid interface. The latter consists of a new repulsion mechanism that, unlike the wellknown Lennard-Jones model, induces no pressure oscillation close to the wall. This hybrid boundary treatment technique is implemented in conjunction with a parameter-free SPH scheme to provide a Lagrangian solver for 2D Navier-Stokes equations. The accuracy of the model is veried by recourse to challenging numerical tests in free surface hydraulics, including a dam break surging over a dry bed, with and without obstacles, as well as a free falling water jet from a sharp-crested weir. Comparison with relevant numerical and/or experimental data from the literature shows fair agreement in each case.