Impacts of bed roughness and orientation on hydraulic jump: A review

Hydraulic jumps are a prevalent phenomenon in flows through spillways, chutes, and sluice gates. As hydraulic jumps exhibit substantial kinetic energy, the downstream of a hydraulic structure is prone to scour. To mitigate downstream scour and enhance energy dissipation, hydraulic jumps are often directed into stilling basins with various bed configurations, including horizontal, sloping, rough, and their combinations. This review compiles numerous analytical and experimental studies on hydraulic jumps under various bed conditions. The effect of bed roughness on sequent depth ratio, roller and jump lengths, shear stress, and energy dissipation is critically reviewed. The impacts of roughness height, flow Froude number, and bed angle on jump characteristics are discussed, substantiated by comparative analyses for distinct roughness heights. The results indicate that bed roughness intensifies shear stress, resulting in augmented energy dissipation and reductions in jump length and sequent depth. Additionally, the analytical and empirical equations proposed by researchers for different jump scenarios are discussed, and their applicability under various conditions is summarized. Finally, it suggests considering the scale effect in future research to refine the comprehension of jump stability over adverse slopes.