Hydraulic jump simulation by SPH

In a hydraulic jump, a supercritical open-channel flow dissipates a large part of its kinetic energy, usually through a strong turbulent roller, and turns into a subcritical flow. Several hydraulic phenomena (strong turbulence effects, downstream wave propagation, unsteadiness, air entrainment) characterize the different jump types (undular, weak, steady, strong. etc..) which can occur depending on the value of the upstream Froude number. The hydraulic jump appears therefore to be a suitable test case to validate different SPH models developed to analyse unsteady turbulent open-channel flows. The present paper investigates the influence of numerical parameters and turbulence models by comparing 2D and 3D SPH solutions with reference literature data, as well as with laboratory data. The comparison between SPH and experimental results shows a relevant influence of smoothing procedures and of different turbulence models, such as mixing length or Standard k-ε, on the free-surface profile description; however, the agreement of computed velocity profiles and water elevations with laboratory data confirms the adequacy of the SPH description.