Experimental Investigation of Erosion and Sedimentation at Unequal Bed Level River Confluence

Document Type : Original Article

Authors

1 Ph.D. Candidate, Dept. of Hydraulic Structure. Shahid Chamran University, Ahwaz, Iran.

2 Professor, Dept. of Hydraulic Structure. Shahid Chamran University, Ahwaz, Iran.

Abstract

Unequal river bed level at the river junctions are common in nature. The study of scour and sedimentation at such junctions however have not received the attention of researchers because of the complexity of the experimental setup. In many studies it has been assumed that the bed level has no significant effect on the scour and sedimentation patterns. It has been reported by a few investigators that the flow patterns and the zone of maximum shear stress in junction of unequal bed level is different from that of equal bed level cases. This study investigated the effect of this variable. First the general non-dimensional equations were developed using the dimensional analysis. Many experimental tests were then conducted under three different river bed discordances and different hydraulic conditions. The data from these experimental tests was compared with the results of the previous study. The results indicated that generally as the river bed discordance increases, the scour hole and point bar dimensions decreases. Using the experimental data, the effects of each non-dimensional parameter on scour depth were investigated and finally relations were developed for prediction of scour dimensions.
 

Keywords

References

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Iran-Water Resources Research
Volume 5, Issue 1
June 2009
Pages 69-78

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History

  • Receive Date: 11 March 2008
  • Accept Date: 09 March 2009

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