A Laboratory Study on the Effect of One and Two Perforated Sills from the Beginning of the Stilling Basin on Head Loss and Hydraulic Jump Characteristics

Document Type : Research Paper


1 M. Sc. Student, Faculty of Water Sciences Engineering, Shahid Chamran University of Ahvaz, Iran.

2 Faculty of Water Sciences Engineering, Shahid Chamran University of Ahvaz, Iran.


There are different types of stilling basins, including the standard stilling basin USBR, stilling basin SAF, the stilling basin with a continuous sill, and the stilling basin with perforated sill noted. Each basin, depending on the intensity of the hydraulic jump, usually needs components to reduce the length of the hydraulic jump as much as possible while shaping it at a specific location. These components include the chute block, baffle piers, and perforated sills that are the subject of this study. These types of dampers are the most common energy dampers in dams and irrigation and drainage networks, and they generally have a high efficiency of over 60% in energy dissipation. The purpose of this study is the evaluation of one and two perforated sill(s) in the stilling basin and its impact on characteristics of the hydraulic jump, such as the length of the hydraulic jump, the dissipation of energy, and the required tailwater depth, and also, to determine the optimal distance of one and two perforated sill(s) from the beginning of the stilling basin with a fixed height for the perforated sill and ratios of the opening of holes equal to 50%.


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Volume 42, Issue 3
October 2019
Pages 47-60
  • Receive Date: 24 April 2017
  • Revise Date: 17 October 2017
  • Accept Date: 21 October 2017
  • First Publish Date: 23 September 2019