Effect of Triangular Corrugated Bed on Hydraulic Jump Characteristics

Hydraulic jump in stilling basins is used for the dissipation of excess kinetic energy downstream of hydraulic structures such as drops, spillways, chutes and gates. In the present research, the hydraulic jump characteristics were experimentally studied over six triangular corrugated beds in a flume of rectangular cross section at the Hydraulics Laboratory of the Department of Water Engineering, University of Shahrekord, Iran. The flume has the dimensions of 0.4 m wide, 0.4 m deep and 12 m long. A total number of 42 tests were carried out for a range of initial Froude numbers from 6.1 to 13.1. In all of the tests, the main characteristics of hydraulic jump including conjugate depth ratio, length of jump and length of the roller were measured. The dimensionless hydraulic parameters were determined as a function of the Froude number. The results showed that the tailwater depth and the length of the jump on triangular corrugated beds are smaller than those of the corresponding jump on a smooth bed. Comparison of these parameters with the same parameters in smooth bed hydraulic jump showed that the conjugate depth and the hydraulic jump length decreased by 25% and 54.7% respectively. The analysis and comparison of the shear stress coefficient showed that shear stress on corrugated bed is about 8.5 times that of smooth bed. The conclusions drawn from the research showed that there is a good agreement between the persent study results and earlier works. Consequently the triangular corrugated beds could be used to dissipate the excessive energy of the hydraulic jump in stilling basins.