HYDRAULIC JUMP CHARACTERISTICS FOR DIFFERENT OPEN CHANNEL AND STILLING BASIN LAYOUTS

Hydraulic jump is considered as the best way for dissipating energy present in moving water downstream of hydraulic structures. This paper conducted laboratory experiments to investigate the hydraulic jump characteristics variations for different rectangular open channel layouts. In this paper, the used open channel layouts were five bed slopes of 0.0175, 0.0349, 0.0524, 0.0699, and 0.0875, and a sill with three different heights was placed along a model of the stilling basin at three different longitudinal distances. The characteristics of the hydraulic jump, which was formed downstream vertical gate, were measured for variable discharges. Results of experiments show that, the hydraulic jump ratios, jump length and initial depth ratio, Lj/y1, jump length and sequent depth ratio, Lj/y2, jump depths ratio, y2/y1, y2-y1, and relative energy loss and initial energy ratio, DE/E1 increase with initial Froude's number for different bed slopes. On the other hand, results show that, the sill has significant effect on the energy dissipation. A new equation was developed to design stilling basin, i.e. the sill height, H, and the longitudinal distance, LB.