Mohammad Vaghefi

This study focuses on the experimental investigation of an inclined circular labyrinth weir with angles of inclination of 60, 70, 80, and 90 degrees. Additionally, the influence of different weir diameters (15, 20, 25, and 30 cm) under various flow rates on hydraulic performance and the discharge coefficient of the weirs were examined. Experimental results revealed that the flow over the weir initially exhibited a free flow type, transitioning to submerged flow as the flow rate increased. No air infiltration into the flow was observed. Moreover, an increase in the dimensionless ratio of the total hydraulic head to the inclined labyrinth weir’s height led to a decrease in the discharge coefficient. The inclined weir with an angle of inclination of 60 degrees exhibited the highest discharge coefficient, while the vertical weir had the lowest coefficient. The analysis of weir diameter showed that although the initial highest discharge coefficient occurred at a 15 cm diameter, further variations in the discharge coefficients among different diameters were minimal, indicating an insignificant effect of weir diameter on the discharge coefficient. Overall, this study provides insights into the hydraulic behavior and discharge coefficient of inclined circular labyrinth weirs, contributing to the understanding and optimization of their performance in water management systems.