Effects of various backward-facing steps on flow characteristics and sediment behaviors

The study of flow over various steps behind the hydraulic structures, such as weirs, dams, spillways, barrages, and flood gates, is still particular interest to researchers due complexity characteristics sediment behaviors at near-bed region. This investigates effect inclined backward-facing step (BFS) angles on turbulent structures bedload transport rate in surface jet regime. A combined numerical technique large eddy simulation discrete element method, based open sources package OpenFOAM, employed. validation model shows a good agreement between results observed data obtained from different experiments. reveal that does not form separation zone when BFS angle less than 20°, wherein turbulence intensity insufficient induce substantial movements. As increased certain value (20°), formed. Consequently, significantly splat effect, flux also drastically increased. further increases 30° 90°, reattachment length extended without notable changes maximum near bed. peaks mean are located downstream along length. quadrant analysis for performed quantify interactions movement. demonstrate sweep event plays significant role moving most point. On other hand, right upstream point, burst becomes dominant move majority backward direction.