SPH modeling of dam-break bores on smooth and macro-roughness slopes

Understanding the kinematics and hydrodynamics of long waves in nearshore zones is currently one of the more pressing aims motivating research in the coastal engineering community. Owing to the simplicity of its setup, the dam-break mechanism is frequently adopted in laboratories to generate bores and model long-wave dynamics, kinematics, and runup processes in coastal regions. Numerical simulations have been used to replicate the results of laboratory experiments using a dam-break system. In this study, we aimed to evaluate the effect of different macro-roughness slopes owing to dam-break driven swash using an open-source particle-based program, DualSPHysics, based on smoothed particle hydrodynamics. To serve as a reference case, the swash flows of a dambreak-generated bore on a uniform slope were performed, and model–data comparisons were made for time-series analysis of the surface elevation, runup process and velocity profiles at selected points. Simulations of dam-break bores passing over slopes containing various configurations of macro-roughness elements were performed to replicate long waves impacting an array of structures in a waterfront area. Different configurations of slope roughness have varying effects on the flow hydrodynamics in the swash zone, which were examined in this study.