Numerical simulation of shallow-water dam break flows in open channels using smoothed particle hydrodynamics

A meshless numerical model is proposed to investigate shallow-water dam break flows in 1D open channels. The numerical model is to solve the shallow water equations (SWE) based on smoothed particle hydrodynamics (SPH). The concept of slice water particles (SWP) is adopted in the SPH-SWE formulation. The numerical sensitivity analysis is first performed to study the appropriate SWP number and variable smoothing length through dam break flows in an idealized 1D channel with dry/wet beds. Extensive validation by comparison with laboratory and field data is next conducted for four benchmark problems, including dam break flows through a rough flat channel, a rough bumpy channel with various downstream boundary conditions, a nonprismatic channel, and a realistic scale model of the Toce river in Italy. The simulated results indicate that accurate performance is reached in the presence of shock discontinuities, shock front motion, hydraulic jumps, dry/wet bed flow, supercritical/subcritical/transcritical flow, reverse flow, contraction flow, overtopping flow, partial reflections and multiple wave interaction without special numerical treatment. All of the simulations are carried out by PC within 10 min. Thus, the proposed numerical model has proved its efficiency and reliability for dam break flow computations in open channels.