SPH simulations of a vertical 2-D liquid jet introduced from the bottom of a free-surface rectangular tank

This paper presents 2-D Smoothed Particle Hydrodynamics (SPH) simulations of a vertical plane jet introduced from the bottom of a finite-depth laterally-confined water environment. Numerical results are compared with experimental observations collected on a free-surface tank of fixed length (1000 mm) and thickness (30 mm); the jet width was kept constant too (21 mm), while the water level varied in a narrow interval (113-130 mm) as a consequence of the inlet jet velocity (ranging between 0.46 and 1.40 m/s). In this range of parameters, the interaction of the jet with the free surface strongly affects the flow development. For inlet jet velocities below the critical value of 0.62 m/s, a stable and symmetric distortion on the water surface is observed. As the inlet velocity exceeds this threshold, the jet starts to flap regularly in horizontal direction. In this case, the mentioned distortion oscillates synchronically with the jet, inducing surface wave propagation. Numerical results show that SPH is adequate to capture the essential features of the observed flow, i.e. the different flow patterns generated by the interaction of the jet with the free-surface as the inlet velocity varies in the mentioned interval.