Numerical Simulation of Side Slope Effect of Main Channel Wall on Flow Behavior in Open Channels Junction

Document Type : Original Article

Authors

1 استادیار گروه مهندسی آب

2 Assistant Professor of Water Engineering. Department of Water Sciences and Engineering. Faculty of Agriculture. University of Kurdistan, Sanandaj, Iran.

Abstract

Appearance of erosion hole and depositional bar has is directly related to hydraulic condition around the rivers confluences zone. In this research, flow pattern in open channel junction was 3D simulated by Fluent and using experimental data. In the experimental study, effects of a 45o side slope in main channel on hydraulic characteristics of flow were investigated and compared with those at a 90o side slope. In this research, furthermore 90o and 45o side slopes, flow patterns of 60o and 75o side slopes were simulated for the same hydraulic conditions. Prediction accuracy of flow field by the numerical model was acceptable and maximum error of simulation was seen around the junction area. Computational error average of velocity for 45o and 90o side slopes were achieved 7.06% and 9.86%, respectively. Results showed falling of water profile surface at avalanche face became milder by decreasing of side slope angle of the main channel wall. The falling values of water profile surface at avalanche face for 90o, 75o, 60o and 45o side slopes were achieved 1.34%, 1.13%, 0.90% and 0.68%. Moreover, by weaken of circular flows, length and width of the separation zone became larger near the water surface. Also, unlike the perpendicular wall, near the bed was not seen a specified separation zone for the inclined walls.
 

Keywords

References

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Iranian Journal of Irrigation & Drainage
Volume 11, Issue 6 - Serial Number 66
March and April 2018
Pages 1024-1037

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