Flow Measurements in Trapezoidal Free Overfall Channels

The drop structures are considered the most well-known aspects of the hydraulic structures being deployed in the channel irrigation systems, in water circulation, in sewage collecting networks, and in addition to the stepped spillways at the modern time. They are used as grade control structures needed to control channel degradation. Nowadays, overfall studies are very important because they can be assigned as discharge measurement devices where its obstacles have been closely studied in the last seven decades. The present research has been taken up as a contribution toward a better understanding for the effects of the side slopes, bed slopes, and bed roughness on the performance of the flow over a free overfall in trapezoidal channels. The present investigation aims to provide relationships for the estimation of flow rate using brink depth and taking into account different effective parameters which are expected to affect the discharge measurements in free-fall of trapezoidal rough channels.