Study Downstream Scour of Rectangular Labyrinth Weir with Gate

Gohari, Saeed; Kabiri, Zahra

doi:10.22092/idser.2018.122111.1326

Document Type : Original Article

Authors

saeed gohari ¹
zahra kabiri ²

¹ Hamedan-Bu-Ali Sina University-faculty of agriculture-department of water science engineering

² bu Ali sina university

https://doi.org/10.22092/idser.2018.122111.1326

Abstract

Labyrinth weirs can be used to increase outlet capacity for a given spillway crest elevation and length or to increase storage by raising the crest while maintaining spillway capacity. Downstream scour dimensions of spillway are important parameters in designing of this structures. By combining the spillway and the gate, two major problems of sedimentation on upstream of spillway and the accumulation of waste materials can be solved. In this study, totally 12 experiments were carried out in 3 different discharges, 10, 15 and 20 liters per second. In this study overflow and flow simultaneously from top of weir and gate for two linear and labyrinth spillway were explored. A layer sand with d50=1 mm and thickness of 15 cm were covered at downstream apron to make a mobile bed. Results showed that by increasing the particle Froude for a constant depth, the maximum scour depth and scour hole length increased. Also it was found that when the flow passed through the spillway and gate simultaneously, in both labyrinth and linear spillway, the maximum scour depth and scour hole length increased with respect to discharge. Transverse profiles at the maximum scour depth also showed that there was a relative symmetry in the case of a linear spillway without a gate, and in this case the bottom profile could be considered as two-dimensional. The maximum scour depth and scour hole length increased with increasing discharge, and its magnitude in labyrinth spillways, was less than that in linear spillways.

Keywords

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Irrigation and Drainage Structures Engineering Research

Study Downstream Scour of Rectangular Labyrinth Weir with Gate

References

References

Volume 20, Issue 75 - Serial Number 75
August 2019
Pages 85-100

Study Downstream Scour of Rectangular Labyrinth Weir with Gate

References

References

Volume 20, Issue 75 - Serial Number 75August 2019Pages 85-100

Volume 20, Issue 75 - Serial Number 75
August 2019
Pages 85-100