Discharge Estimation in Compound Channels with the Use of Diagonal Dividing Lines

Document Type : Research Paper


1 Assistant Professor, Department of Water Engineering, Faculty of Agriculture, Lorestan University.

2 Ph.D. Student, Department of Water Engineering, Faculty of Agriculture, Lorestan University.

3 Associate professor, Department of Water Engineering, Faculty of Agriculture, Lorestan University.


Based on the previous research, the flow rate estimation by the DCM method has been widely used in compound channels and many computational models have been developed accordingly. Therefore, a compound channel dividing into sections according to the most accurate method is a requirement that all researchers agree. While vertical lines are used in models for dividing the compound channel into the main channel and floodplain, some researchers maintain that vertical lines have an inaccurate performance compared with horizontal and diagonal lines, especially for low discharge (Khatua et al., 2013, Mohaghegh and Kouchakzadeh, 2008, and Ozbek et al., 2004). However, the methods for discharge estimation based on the shear stress calculation uses vertical lines (Ackers, 1993, Shiono and Knight, 1991, and Bousmar and Zech,1999). In this research, it has been attempted to present the best angle of the dividing line, which results in a 0% error rate calculated by comparing the effect of dividing lines with different angles on the calculation of the discharge of the compound channel.


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Volume 42, Issue 3
October 2019
Pages 163-177
  • Receive Date: 15 June 2017
  • Revise Date: 12 December 2017
  • Accept Date: 16 December 2017
  • Publish Date: 23 September 2019