Document Type : Research Article

Authors

• Fatemeh Asgharinejad ¹
• Mohammad Hemmati ²

¹ water eng. dep. Urmia Un.

² Associate Prof., Water Eng. Dep., Urmia University, Urmia, Iran

Abstract

The study explores the intricate dynamics of flow at river confluences, focusing on the impact of changing the side slope of the tributary canal wall on the flow patterns. Using the Flow-3D model, the research investigates the influence of the side slope angle (Z), discharge ratio (Qr=Q2/Q3), and Froude number (Fr) on the flow dynamics at river confluences. To achieve this, the study considers various angles for the side slope, different discharge ratios, and Froude numbers in a confluence with a 90-degree angle. The findings reveal that altering the lateral slope of the tributary canal wall significantly affects the flow pattern, leading to changes in the length and relative width of the separated flow zones. The augmentation of the lateral angle resulted in a proportional escalation in the length of the separation zone contiguous to the water surface. Nevertheless, the comparative width of the separation zone and the relative water level at the inclinations of 60 and 75 degrees surpassed those at 45 and 90 degrees. Moreover, the incline of the walls at 60 and 75 degrees resulted in a 32% increase in the water level upstream of the confluence, as compared to the downstream.

Keywords

• flow dynamics
• river confluence
• side slope
• separation zone
• Flow-3D

Main Subjects

• Hydraulics