Abstract:
In this study, a total of 57 tests were performed to investigate the effects of three relative roughnesses (0.51, 0.86, 1.34) and six slopes (−0.02, −0.03, −0.04, −0.05, −0.07, −0.10) on the hydraulic characteristics of F-type jumps over adverse-sloped sinusoidal-corrugated beds, whose Froude Number ranged from 5 to 11. The experimental results show that compared to the classic hydraulic jump and the F-type jump on the smooth bed, the adverse-sloped sinusoidal-corrugated bed can effectively reduce the roller length and sequent depth ratio. And the rough bed is beneficial to stabilize the F-type jump. The velocity profiles are more sensitive to the relative roughness than the slope, and the relative roughness affects the similarity of these velocity profiles and the development of boundary layer thickness. The velocity profile is most uneven near 0.4 times roller length away from the initial point of the F-type jump. After 1.2 times the roller length, the momentum correction coefficient of the profile is almost 1.0. The shear force coefficient of the adverse-sloped corrugated bed is 10~16 times that of the horizontal-smooth bed, which indicates that the adverse-sloped sinusoidal-corrugated bed is very effective in energy dissipation over short distances.