Numerical modeling of dambreak-induced flood and inundation using smoothed particle hydrodynamics

Smoothed particle hydrodynamics (SPH) is used to solve the two-dimensional shallow water equations (2D-SWEs) for modeling dambreak-induced flood and inundation. The Lagrangian concept of cylindrical water particles (CWPs) is adopted to generate horizontal flows in rivers and floodplains. Parameter sensitivity analysis and model validation are described to demonstrate the benefits and limits of the 2D-SPH–SWE modeling. Particular attention is devoted to the numerical performance of dealing with free-surface discontinuities, different upstream/downstream boundary conditions, wetting–drying moving interfaces, river–floodplain roughness sensitivity and complex topography variations. The simulated results indicate that many complicated flow phenomena occurred in dam break flows such as transcritical mixed flows, shock front propagation, overtopping flows, partial reflections, hydraulic jumps, hydraulic drops and multiple wave interaction, can be faithfully simulated. Thus, the proposed SPH approach has proved its robustness and reliability for 2D flood and inundation simulations, and can provide an alternative to investigate practical hydraulic engineering problems.