Experimental Study of Flow Characteristics Through Sluice Gates in U-Shaped Channels

【Objective】 Flow measurement through sluice gates in U-Shaped channels depends on a range of factors. We experimentally measured the characteristics of flow through the gates under different designs and working conditions, and then derived a formula using these data to estimate flow rates based on hydraulic characteristics of the gate and channel, as well as the working conditions. 【Method】 The experiments were conducted by controlling the flow rates from 10 to 50 L/s. The critical ratio of orifice flow to weir flow, as well as the flow capacity were analyzed utilizing hydraulic parameters, including water surface line, Froude number, and water head loss across the gate. These parameters were used in the orifice flow formula to calculate the flow rate. 【Result】 The critical ratio of orifice flow to weir flow was close to 1, the Froude number was uniformly distributed along the flow path, and the average relative head loss across the gate was 7%. Compared to the measured data, the error of the derived formula was less than 3.5%. 【Conclusion】 The sluice gate for the U-Shaped channel works well, and water head loss across it is minor. The derived formula for calculating flow rate is accurate. These results are helpful for designing U-shaped channels in irrigation areas and calculating flow rates through them.