Effect of Sinusoidal Corrugated Bed on Hydraulic Jump Characteristics

Document Type : Research Paper

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Abstract

In the present research, the experimental study of the hydraulic jump  within a wide scope rather than those of other researchers was implemented on  six corrugated beds with different wave steepness. The wave steepness of corrugations and the Froude number were in the range of 0.286 to 0.625 and 3.8 to 8.6, respectively. The effects of wave height and length of corrugations on the basic character of the hydraulic jump such as free surface location, velocity, shear stress distribution and energy dissipation were studied for different Froude numbers. The dimensionless hydraulic parameters were determined as functions of the Froude number. The results showed that the tailwater depth and the length of the jump on corrugated beds were smaller than those of the corresponding jump on a smooth bed. The analysis of velocity profiles at different sections of the jump showed that the velocity profiles were similar and differed from the profile of the simple plane wall jet. The normalized boundary layer thickness, was equal to 0.57 for the jumps on corrugated bed compared to 0.16 for the simple wall jet. The analysis and comparison of the bed shear force and shear stress coefficients showed that the shear stress on the corrugated bed was about 10 times greater than that of the smooth bed. The results of this study are in good agreement with the previous results and showed that the corrugated beds could be used to dissipate efficiently the excessive energy of the hydraulic jump in stilling basins.

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