Hydraulics of Rotary Gate: Novel Structure for Semicircular Canals

Abstract

In this study, a new structure named a rotary gate is introduced to control and measure the flow in canals having a semicircular or semielliptical cross section. A pivot rod, connected to the centerline of the gate and to its frame, holds the gate in place and acts as a hinge for the gate rotational movement. The gate is easy to maneuver and requires a rather small force for its movement, which makes it appropriate for network automation. The hydraulic properties of the rotary gate were investigated during an intensive experimental study and presented in this paper. Influences of the gate opening angles on the flow depths, discharge measurements, and discharge coefficients in free flow were studied using different approaches, and the results of developed relationships were evaluated. Finally, a relationship to determine the relative head loss of the gate according to the relative opening and the relative discharge was proposed.