Numerical Simulation of Chute Energy Dissipation with Submerged Cylindrical Obstacle using Flow 3D Model

Document Type : Research Paper

Authors

1 Ph.D. Candidate, Civil Engineering Department, University of Sistan and Balouchestan, Iran

2 Assistant Professor, Civil Engineering Department, University of Sistan and Balouchestan, Iran

3 Ph.D. Candidate, Civil Engineering Department, University of Sistan and Balouchestan, Iran.

Abstract

In general, the energy dissipating structures are used in order to prevent the destructive effects of high flow velocities through the spillways. Among these structures, the most commonly used structures are chutes in water conveyance systems in dams, irrigation and drainage networks, alluvial rivers and wastewater collecting and disposal systems. The energy dissipating structures are used at the downstream of this systems. The advantage of this method to the previous methods such as stepped spillway is that the risk ‎of ‎cavitation is less and it is more economical. ‎One of the ways to reduce the size or eliminate low energy dissipating structures is to use methods for reducing the flow energy over the chutes. One of these techniques, which has been used so far, is to create steps over the spillway. Another method is the application of obstruction or roughness on the spillway’s bottom. Baffled chute is a type of the dissipaters that is used extensively in open drainage networks and where the tailwater level has large fluctuations. The significance of this type of energy loss becomes more evident where the tailwater has obvious fluctuations. The purpose of this study is to numerically simulate the effect of cylindrical baffles over the chutes on the energy dissipation magnitude. In particular, the purpose of this study is to determine whether the cylindrical baffles can effectively reduce the kinetic energy and reduce the dimensions of the stilling basin.

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Volume 41, Issue 4
January 2019
Pages 17-28
  • Receive Date: 30 May 2016
  • Revise Date: 15 December 2016
  • Accept Date: 18 December 2016
  • Publish Date: 22 December 2018