Experimental and Numerical Investigation of the Effect of Transition Length on Energy Losses in Gradual Transitions Open Channels Under Subcritical Flow

Document Type : Research Paper


1 Ph.D. Candidate of Civil Engineering, Hydraulic Structures, Razi University, Kermanshah, Iran.

2 Assistant Professor, Department of Civil Engineering, Razi University, Kermanshah, Iran

3 Associate Professor, Department of Water Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.

4 4- Professor, Department of Civil Engineering, Razi University, Kermanshah, Iran.


'Transition' is a short hydraulic structure used to change the cross-sectional shape or flow shape. Transitions are commonly used both in the open-channels and natural waterways. The task of a transition is to connect a narrow channel at the upstream to a wider downstream channel or vice-versa. This, creates a disturbance region of turbulent flow causing energy losses. In general, the structure of a transition prevents the formation of wave and other turbulencies. In this case, the energy loss, due to the change in the amount of the momentum, will be minimized.


Main Subjects

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Volume 41, Issue 2
June 2018
Pages 45-59
  • Receive Date: 02 January 2016
  • Revise Date: 20 November 2016
  • Accept Date: 04 December 2016
  • Publish Date: 22 June 2018